very few "vendors" will ever precompile and package applications or modules for specific distros. it's usually seen with the more mainstream ones, such as fedora or ubuntu, but it's not so common.
most distros just create packages for their repo's using the source code and having a maintainer take care of the compiling and packaging so that end users don't have to. it's no different here, it's just that whoever it is that's coded this linux port for zfs has decided to provide pre-compiled packages for these two popular distros. other distros will probably provide the same packages, only they will have to be maintained by the distro's themselves. or, as it is always possible should your distro of choice decide not to pick up the module, or if you want to it yourself, compiled and installed directly by the end user.