I really only enter the sweeps I am interested in and if I have won something I want then I normally won't enter again. For instance I won a guitar I don't enter again. I don't enter brides sweeps because I am not a bride. I also don't enter trips because I don't want to.
I think people will enter sweeps for many reasons and that's up to them as to how they feel about the sweep they enter. We are all going to be different on this one and that's to be expected.
I say to each his own and I won't worry about anyone else because I have enough to worry about on my own. I also can see both sides to the issue though and so I agree with everyone on this one.