No joke, I did that last weekend when they weren't home! I feel so bad, but hey...they need to get out and do their part to!
I don't blame you at all.
I would probably never rake anything on my own, but if it affected my neighbors, I'd do it just because I wouldn't want to be THAT neighbor.
One of the first houses we owned had a beautiful front yard that turned out to be much more work than we realized. If it were up to us, we would've let things go, but we didn't want to be the jerks who made the neighborhood look bad. We liked that house a lot, but the next place we bought, we made sure there was way less yard work, lol.