If the owner of the guild stops giving them out, you should feel free to stay. If they do not care and wish to continue, it is up to you but I have heard of entire guilds getting punished. Chances are, though, if TNT does anything about it, only the owner and/or council will be punished.

You would be allowed to accept them... from a "side account'" point of view. It's only Neopets regulated stuff that you can not double up on. I would not accept them in general, though, because if you know they are against the rules, and accept them, you are just as guilty as the person who gives them out, much as the person who pays for services on the site, knowing it isn't allowed is as guilty as the person who asked for payment.

Remember: Gifts are great, prearranged payment/ giveaways are bad.