I voted no on this poll.
"OMG NO WAI! U voted no?!!!1
Yea, you see, I personally think that webcomics are designed to entertain yourself and your readers, instead of making money off them. Sure, people would like to buy some things, but it wouldn't be the first time that I've seen webcomics getting less funny once the authors started to make a decent living out of it.
I do support donate buttons though, because the readers can decide how much to give themselves, and it helps them to maintain the website (in case it requires a fee to stay online).
Plus, I never buy anything from the internet anyway.