I really think players should take advantage from the free rolls, and start making their bankroll from scratch like that, but they need to step up eventually. It's very hard to play in freerolls or low stakes. Players have nothing to lose, and yes you can beat them in the long term, but the problem is that you can't beat them all.
In low stakes and freerolls it's easy to see players going all in all the time, and since they are many doing it, you will lose eventually. Since it's free, most of the players will continue playing like that, meaning that you will have a hard time progressing and testing your strategy, and you will need more luck than you should. So after building some bankroll, you should always try to go up in the stakes, in order to be able to play vs serious opponents.