@gollum,
I know when I was in college, I got an absentee ballot. I was able to go to my registrar office and vote, they recorded/signed off it was valid and I sent it in.
I think it makes sense, if someone is unable to get out to vote on voting day, say you are elderly, there is something in place where they are able to vote without physically go to the voter booth.
Some sort of in between, where the general public can feel there is some sort of protection of voter fraud. Maybe a the head of an assistant living facility is given authority to signoff (similar to a college registrar). In reality one, if they wanted and knew when these ballots are mailed, go to various mailboxes and take them and use these ballots to vote.
Do I think there is widespread voter fraud? No, but perception may be otherwise and if it is perceived that this could result in voter fraud, why wouldn't we want to put in place some safety nets? Just common sense. Where I work, I cannot get presents of a certain value from a parent, why? So it is not perceived that I give their child better treatment than another. Although there would be no reason to suspect this, it could be perceived I am being bribed.
We do it in other areas, why not voting ballots?