I'm just asking out of curiosity...
I can't imagine why anyone would want to download a game more than once...
Any idea?
If there are several downloads in a row, it is probably due to a download error, Itch counts as a download every time you start a download and not when it finishes correctly.
Personally, it has happened to me with games that use a lot of space, to have an error in the middle of the download. I have to start the download again and in some cases it has happened to me 5 or 6 times in a row, the developer will see 5 or 6 downloads, but I really only downloaded the game once.
It can also happen that you download the game on more than one computer and people are more used to re-downloading the game, instead of backing up and moving the file. The same thing happens if you have to format the PC, people do not back up the game, but people are more used to downloading it again.