Those that want to debug distribution provided packages. To report a bug, to profile a performance issue, to use valgrind. I am by no means saying that a everybody would use these tools, but for those that want them, their lack is very inconvenient.
Debian also has experimental, testing, and unstable branches, which are comparable to arch linux. And those branches also have debug data support via debuginfod.
OpenSUSE Tumbleweed is also pretty much a rolling distribution. It also has a debuginfod server. Same with Artix Linux, Void Linux.