I never used to "collect" ammo (.22 or otherwise), but ever since it got so darn expensive, I tend to make sure I have "enough" on hand.
I don't want to go through the shortage period again and not be stocked enough to get through.
That said, I mainly keep up the stock of CCI SV for the target pistols, and then any of the other hi-velocity loads for the .22 rifles and revolvers.
One of my latest unintended acquisitions was a Christmas gift from my brother in law of a some .22 tracers.
I don't know what I will shoot them out of for fear of barrel damage (just my fear, maybe not a reality), but they'll be fun to mess with some late evening one day in the future.