I dropped off my wife's ballot. It is totally normal for one person to drop off multiple ballots at the box. It would even be hard for you to notice multiple ballots being dropped. I did our two with one gesture.
The vote buying cow has already left the barn.
So it's far more important to let citizens verify that their vote was counted accurately, with some sort of anonymizing hash.
I did the same thing with my wife's ballot this morning, and I saw multiple other people dropping more than one ballot as well.