Quoting Al Nikolov <clown@debian.org>:
This is only partially true: nothing is preventing anyone to create their own service and reuse the same client software.
I was under the impression that their server name is somehow hardcoded into the software.
Moreover, it doesn't require to use any service at all and can function without reporting any data gathered to anywhere but to standard output/journal.
If the software makes sense without any proprietary service, then it fits in main, of course.