I signed up with them over a month ago and have yet to receive any unsolicited emails as a result. You have to provide the usual info you would normally have to provide when linking to a bank account. I was not asked for scans of any documents. If you don't want to sign up, then don't. They are just offering a service by which you can transfer funds from a bank account to the ripple network. What's the big deal?

Now, whether or not it is a good idea to be dumping funds into the ripple network is an entirely different debate, but I don't see the problem with what SnapSwap is doing...