For a marketplace that doesn't support bitcoin sales, there sure are a hell of a lot for sale there. I'm pretty sure that rule is untrue or not enforced.

Would I buy crypto on eBay?  Not at the prices you generally find there. I haven't actually checked in a while, but it used to be like buying from wesellcrypto.com--a really high mark up and not worth it. Seems like it'd be fairly safe if you paid with PP but I've never done it.  As mentioned, you can find good deals right on bitcointalk.