Another reason for single-file distribution is the ease of installation and running. If you can run from a single executable with all resources embedded in it,

Another reason for single-file distribution is the ease of installation and running. If you can run from a single executable with all resources embedded in it, then users have a very easy time of things, they just download the program, then run it. Apple's ".app" distribution format works just like that, while allowing the developer to have a directory structure for their convenience. App stores solve the problem in other ways, but there is no good app store for the web.