Always seemed a bit of a weird cartridge to me.
If you wanted to massacre squirrels and rabbits at a farther distance than .22LR allows I suppose it's a good choice. It costs more than basic 9mm FMJ though, which kinda blows my mind.
I have a couple 17 HMR rifles and my kids absolutely loved them when they were Growing up. I also have a 17WSM which I find a whole lot more fun than the HMR.