This isn't racial profiling. An unverified account can pretty easily be changed to verified by the vast majority of SL players (who tend to own reasonably fast computers and subscribe to broadband services, and thus have payment info readily at hand).
This is true for nearly all US members. It's actually hard to subscribe to broadband services here without a credit card; some providers don't take any other form of payment.
But the picture is very different for some of our international users. Credit cards are not ubiquitous in all the world. And if you do have one, the transaction fees for US$ transactions can be prohibitive. (I've seen reports from here in the forums about costs of about US$20 to make a payment to LL -- that's on top of whatever amount of money they're actually trying to pay.)
So, yes, the net effect is that any ban on unverified members DOES become, in effect, racial profiling of a sort. I recommend thinking really hard before taking any such action.