When was the last time you went back to base and had 75 gold and an inventory slot?
It's probably about 90% of the time. Especially early game. So hey buddy, but some wards™. That with 150 gold for 2 wards™, you can deny the enemy a way to gank you, meaning you have spent 150 gold to avoid giving the enemy 300. Meaning that puts your team ahead 150 gold.
BUT WAIT!
You can also buy a 
to kill enemy wards™, meaning now they are out 150 gold, and you just gained 60! And your jungler (assuming you aren't shoving to tower like a dick and they also aren't a tank or someone who can dive) can now gank them, meaning you get 300 gold! And the person who doesn't get the kill still gets 150!
Wards™ save lives. You place a ward™ in the river, oh shit Pantheon is ulting bot! Good thing we saw him from Bae 
so now he's wasted his time and his ultimate, because you had vision. With vision, you could see the enemy low at their blue buff, sweet! Free kill and a buff!
And for just 100 gold you can buy our special PINK EDITION! 
Pink Edition Ward™ also grants vision of all stealthed units! That's right fuck you Shaco 
! Additionally Pink Ward™ last forever until the enemy kills it. This mean buying a pink Ward™ first back could lead to a 30 minute Ward™. The Value!
Save lives, buy a Ward™
[Ward is copywritten and trademarked by Rito Gaems. All usage of Wards™ resulting in kills are to provide a 10 gold tax to Rito Gaems. Remember, it's not just map control, it's a Ward™!]
