Because people who aren't sick are getting forced to get tested as a normal seasonal upper respiratory bug is spreading through the population just like they do every year. They're reporting "cases" because the death rate and the hospitalization rate are plummeting. Cases aren't sick people.

This is the first time in history anyone has ever performed mass testing on people who are not sick, so no one has anything to compare it to to say whether these numbers are high or low, but we can now say with absolute scientific certainty that the virus is no where near as dangerous as the panic mongers originally suggested and all of this lockdown nonsense was a complete waste of time.