I've played for years, in locations all across the US, and know many other people who've played much more. This is basically not a thing. I encountered it once, decades ago, at Hawaiian Gardens in SoCal. If it's happening regularly it's very obvious, and the floor will quickly become aware of it. As far as making a living, it's easier to learn how to beat live low stakes than to successfully collude, and the latter would be unlikely to help much if you weren't already beating the games.