A system that tracks what store items you might be interested in, and places you in matches with high-skilled players who own that item, making you associate the item with high skill
A system that places you against lower-skilled opponents immediately after you bought an item, making you associate making a purchase with being better.
From here to “they want you to look at other players and how expensive their shit is” is only one step. Honestly at this point I’m even surprised they’re not faking it entirely, making other players just happen to be wearing expensive skins on your screen even if the actual account hasn’t bought that. It’s not like you can check anyway.