Platinums and Golds Don't Know How To Ward Either!!!!

So a major problem in me not escaping my elo is wards. I don't ward as often as I should, teams don't ward often period, and so we get caught out a lot. Anyway, I've been playing some normals to learn Rek'Sai, and for some reason I'm paired with high golds low platinums in normals. I'd guess there's a seperate MMR for normals that I've reached, I dunno. So these past few games, nobody has bought a single ward. Only used their trinkets, and they still rarely used their trinkets. What the actual hell? I thought once I reached gold things would be better and easier, but they can't do as simple a task as warding?