I was pissed when Cake Poker
first asked me to do this when I wanted to withdraw.... but I sent them the info and got my cheque soon after.
It sucks, but I think it was....tenbob... he told me that most of the good poker websites
now require this standard check to basically legitly prove that you are a real person with a real address, and not underage etc.
You will encounter this at pretty much every website to withdraw from. Hmmm I withdrew $500 a few times from pokerstars
and they never asked for it though, Stars is the only website I know that does not seem to require this however.