alternatively, you can download love2d from love2d.org. They have an executable using which you can execute .love files.
in fact, "compiling it as an executable for windows" consists of taking one of the executables (love.exe) you can find at love2d.org and simply adding the .love file to the end of the executable.
you have the choice every time you download a game to (1) download this executable file (love.exe) plus the .love file (combined as one big game executable file), or to (2) download the love2d engine from love2d.org once and having all .love files be automatically run with it.
(1) may be more convenient for you at first, but the more games you have which depend on love2d, (2) becomes increasingly more beneficial (it saves space and download time).
In a game jam which is centered around love2d, i think it is quite reasonable to only provide the .love file, and have everything else optional. Installing the love2d engine would also allow you to play (and rate!) all other entries in this jam (such as mine) without depending on the developers to provide a windows executeable (because i don't).