[pillowkusis]

TF2 was one the first major game to introduce a F2P+microtransactions+loot crate economy. I think they did it fairly.

Paid content was always for purely cosmetic changes (with some very small exceptions, removed in 2013). You could pay for items if you want, but they also were granted to you weekly entirely for free.

You could/can purchase every weapon in the game for about $5 total.

I played TF2 at a competitive level for a year without spending a cent on the game.