Well, nobody asked my opinion but I have one.
Several factors are in play.
Restrictive government issues cause folks to worry about supply and demand. So they load up with cases rather than boxes, when they find it.
Hoarding is a factor.

Not everybody reloads and reloading components are just as hard to find as loaded ammunituon.
That makes the lower cost of .22 LR and other rimfire ammunition more appealing. See supply and demand above.

Current popular lust is spray and pray attitude rather than a single well place shot counts too.
Manufactures pander to that notion by making more and faster cycling semi auto .22 rifles.
A guy and his kids can shoot up a rather large inventory of .22 LR in an afternoon without breaking a good sweat.

Result: little or no ammunition on the shelf when you visit. JMHO

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Freedom is not Free!
Charlie