This all depends on each players individual circumstances. If you are depositing frequently, I can only think of two reasons for this:
1. You play big $ games and do not want to leave too many $'s on the site for risk management purposes, so you are depositing and withdrawing frequently. But let's just assume that is not most of us, and move onto the next possibility,
2. You are losing and need to replenish funds. In this case, you need to ask yourself: Can I afford to lose $x's per month, as a) I consider this entertainment expense, or b) am I just chasing a pipe-dream of cashing big and overspending my means?
If your answer to #2 is "a)" there is really no problem, but if your answer is "b)"then you need to take a good hard look in the mirror and re-evaluate things.