TBQH Valve/Steam is a major factor in this gambling in games scene but gamers love them. So I don't think this is the real reason gamers have a problem with EA.

Which Valve game involves a pay-to-win mechanic that affects gameplay?

I don't know about pay to win, but TF2 and CS:Go have had extensive gambling scenes from what I've heard.

My defence with Valve is that at least on their stuff you most of time get stored credit. With the rest it is same, but it is actually drown the drain.

For me, it's their support for linux and their easy return policy for games that don't end up working. Gaben could light an orphanage on fire and I'd forgive him.