if you're an OS X user and you don't have Wine, you're doing it wrong.
I have wine, and I use it all the time
though it is nice to make a port for a game so it is actually recognized as a Mac Application. Also less advanced users may not have that option, and if they do may not want to use it. Having it as a .app file makes it much easier to use, and people like that.
can anyone send a pic of the file icon?