I can see the appeal for removable media, at least. It’s pretty common for those to have only a single user toting them around between home/work/school and for that case it makes a lot of sense to store that info on the media so settings stick across different machines. It probably made even more sense back when removable media was the norm for data transfer because network access was spotty or slow.

It really should be turned off by default on network volumes though.