The game of vision.
Just had a game where a topic came up that I feel pretty strongly about. The topic was; vision, sightstones, and who should and should not get them. Let me preface by saying this was a normal game that we won. The jungler on my team was curious as too why the support had not built a sightstone, to which our toplane said that they(the jungler) could buy one. The jungler seemed to ignore that comment and kept saying that not having vision was making us lose and was going to cost us the entire game, at one point they even refused to fight with the team until the support purchased a sightstone. At no point was our jungler friendly with the support when discussing vision or even helpful, they never upgraded out of their yellow WARD PLACING trinket and kept complaining.
Giving that explain I now would like to say that vision, like League of Legends itself, is a team game. The entire team can provide vision through use of the trinkets, sightstones, and pink wards. There are many ways to provide vision, but it should not be completely dependent on the support. Also if your support is using wards but placing them in spots you don't think are good you can buy a sightstone or similar item and place wards yourself. But do not belittle, argue, or curse out a team mate because of vision. That negative attitude will only divide a team you are with and make it far more likely for you to lose a game you want to win.
Just keep in mind, sightstone is a item that any champion and any role can buy, not just supports.