I'm a support main and I on average buy around 9 pink wards a game. On some days I buy as many as 15. I was wondering if this is too much, since it does give the enemy team gold and exp as well as eating up a lot of my own. Is the vision and vision denial worth it?
Also, should I keep a slot open for Pinks after full build?
You shouldn't be worrying about you buying pink wards get your team to do it.
well if you have the gold to spare then buy one even if you already have one somewhere already. It never hurts to have more in your inventory and if you are clearing another ward then it doesn't matter if it gets cleared. Vision and Vision denial is worth a lot more than anything in the game. It allows you to set up ambushes, let you know when it's safe to take dragon/baron, how far you can overextend, when it's good to take a fight and when it's not... all of that and more!
As soon as the previous one is destroyed. -
Me and this damn Taric are gonna have a fight over river bush, I swear.
Whenever you have pocket space and 75 gold. Also makes a rather good habit.
If you're getting full build, it depends on the matchup. Normally if there's no threats that rely on stealth, no need. Otherwise, it's a pretty good investment.
In laning phase, having 1 in tribush/gromp bush (depends what side of the map you are) is fine.
But once you're in midgame you generally want to be having one in your inventory at all times to replace the lane pink and put it in a better location/replace ones that get destroyed.
If you're full build, you've built a 
Sightstone or 
one of the "Eye of" variants that Sightstone builds into. All of these have a Warding active.
If you have an item with a Warding active (which every support should have early on for reliable vision), you should switch your Trinket up as soon as you buy it. The reason being... what's the use of TWO channels of warding? The yellow trinket's been made redundant.
Sweeping Lens and 
Oracle's Alteration are going to be your new friends in vision denial now and replace the yellow trinket's slot now that it's made redundant.
You get Sweeping Lens when you get your warding item. And then Oracle's alteration once you reach level 9. Oracle's is essentially Sweeping Lens that follows you so you can sweep a whole area rather than just one spot.
That said, just because you have a sweeping trinket before full build doesn't mean you should slack off on buying pinks. Those trinkets get put on cooldown after use whereas pinks are available quickly. But if you're divided between full build and pinks for your sixth slot? Go full build. You're more useful that way. Just use your sweeping trinket wisely.
Vision control is its own little skill in the game and IS worth it once you learn it.
woah that's waaaay too many lol.
i preach buying pink wards like crazy, not as just a support... but as every role... but upwards of 9-15??? lol
unfortunately, silver 5 is an elo where your teammates generally don't even basic ward, let alone pink ward, so a lot of the lack of pinks/vision isn't really on you... however I'd also venture to say that if your wards are getting destroyed that often, you're not using them quite correctly either.
placing them as a defensive ward in your lane bush at the beginning is a good thing, if it keeps getting repeatedly destroyed... yes, you are simply wasting money. because the enemy team knows it's going to be there, and more importantly, apparently CAN destroy it, without consequence.
if you can't defend it, AND lose it constantly... use normal wards, and place your pink elsewhere.
likewise with placing offensive pinks, which you place in the enemy jungle for instance. you should only be doing this if the game is flowing in a way where it's going to help you with more than just spotting the enemy jungler, or as a simple warning. for example... if you have 2nd tier turret bot lane, 1st or 2nd mid, and you guys are relatively ahead... a pink in that side of enemy jungle (near bot) can help get you some picks to close out the game (or knowing when to get objectives elsewhere). whereas normally it might just end up getting destroyed... repeatedly...
nothing wrong with using pinks as bait either though, and well worth the cost if it happens even once. just don't fall for it if it's actually a bait on you... more wards elsewhere help this not to happen, ironically ;P but if you're up that far already, you should have more around anyway.
otherwise, defensive pinks are better... mostly in your own jungle, or the river (a good spot to spot not only the jungle, but potential drake takes, and mid roams). and using yellows to ward anywhere further up than that.
and above all, like i said... ward based on how the flow of the game is going. and ward where your enemies are most likely to show up/be seen. doing this requires a bit more judgement than simple map awareness, but figuring it out can be essential to being a good support.
Buy enough to have one one you at all times and one on the field. Enemy destroys one, buy another. Early game you want to buy one if you go back and do not have enough gold to get an item, or buy a pink and an item, but item comes first.
Ideally everyone should buy one when they can.
Realistically only you and the jungler will be buying them. Try to buy one on your first back, and try to keep it from an obvious spot. If you're getting camped in bot lane on the blue side, feel free to put it in that 3 way bush near you. It's saved my life on more than one occasion. Otherwise keep it out of the river bush if you're on red side because the enemy support is just going to get free 30 gold in a second after you place it down.
If you're under pressure while taking an objective, try to lay a pink down to deny the enemy vision of the objective.
I personally always like to lay pink wards down near blue and red buffs when I can. In the average game usually no one clears them for a while.
It is worth it if you can clear other wards. 30G is not much. It's just 1 CS, the vision and vision denial is far, far more valuable.
Buy it whenever you can, and remember, support's isnt the only one that should be buying pinks cuz you can keep one on the rift. The day where all lanes buy wards use their wards / upgrade to blue trink and pinks will be the day they truly climb.
