8,001 people a day buy 500 rounds and they can't keep up.
That represents 1% of the 80M gun owners of America, not all of whom own .22 weapons. But, if they did, it would mean that it will take any given individual about 100 days to encounter a box of 500 rounds.
Where are the foreign manufacturers and importers while this .22 shortage goes on? There doesn't seem to be any foreign made .22 ammo available either.