I understand those unwilling to deposit, but there are couple of things about depositing that are worth mentioning . . .
Deposits are essential to the survival of a poker site
. It's good that not all players are unwilling to deposit, or there would be no online poker at all. Poker is a zero sum game, as such it is necessary for every dollar taken in rake plus every dollar withdrawn to be replaced by new money (deposits) or the site will die.
Also, consider what your time is worth. If your goal is to make as much money at poker that you can, then making a small investment in yourself is a prudent start.
Ultimately you want to be playing the highest stakes you can beat
, and maintain a bankroll sufficient to play those stakes. That combination will show growth in your bankroll, and you can then move up stakes when it is appropriate.