You CAN wash them, but you don't NEED to (at least, not every time - only when they're really dirty). Just like you CAN wrap your skates up entirely in towels, but you don't NEED to. Some people do have bags made out of towels - they put the whole skate in the towel bag, and then put that in their skate bag. It's possible to buy them ready-made, or people make them themselves out of old towels. But, again, you don't NEED to do that. And, yes, you should be able to buy soakers in any skate shop.