They need to make money to keep their servers up, otherwise, the game was be dead and we'd all be sad. So we need to be dependent on donors, cash shop buyers, and stuff like that. Anyway, TF2 is a good f2p fps. There's no imbalance, everything's fair, good graphics, barely any lag (I don't think you lag if your comp is crap btw), and a good player base. AVA's good too. High player count, good graphics, realistic recoil, decent modifications, and items that upgrade your character (without the need of cash), there's even a reward system.