all butler does is create and upload a zip file - for unity game it does NOT upload all the individual directories/files
These are some pointless semantics. The files and directories are in the zip file, hence they are also uploaded.
so when user downloads the game they get a zip that they must unzip someplace to get the directories/files
Yes, that’s how things are done around here. You can’t expect every person to play your game enough that this becomes a problem. An installer is too much overhead for a game I may play not 10 times in my life.
For people who want long-term installation, they can do it themselves or they have the Itch app. What will you do for the latter? Have them install an installer?