The price difference between bulk and standard 36 exposure rolls isn't significant enough to justify the expense and labor of loading your own if you're not shooting a bunch; if you're shooting 10-20 or more rolls/week the cost savings does start to add up. The real benefit for those of us who shoot less seems to be the ability to load short rolls, say 12-18 exposures, when you have the need for short rolls. Plus I started at uni loading my own when I was studying darkroom, so it was a no-brainer (I'm good at those decisions) to do so again when I got back into it.
There are those who don't need to justify the expense. They like the hands-on aspect of film photography, and loading their own is a part of that. I suspect many of them graduated to LF. I have a certain amount of appreciation for this perspective.