I'm thinking about this. The trouble is, if you sell anything and accept Paypal, you must do this. I've kept an alternate bank account with a very few dollars in it for these transactions, but now that most banks (greedy schmucks) are charging $7 per month for a checking account - unless you keep $1500 in it that scammers can get to in event of hack - this is not an option.
AAARGH! I think you MUST give them a bank account when you get started with Paypal, even if you use a credit card for purchases, right? They always try to steer you away from your credit card in an attempt to avoid the merchant fees, and to encourage you to keep money in your Paypal account that you don't receive interest on, too.
See if you can get into a local credit union or something. They are much better than the big banks regarding fees, minimum balances, etc.