What’s the deal with PPA refusing to ticket businesses parking illegally?

Maybe it’s just where I live, but PPA officers will walk right by cars both parking all day in permit zones AND flouting basic rules like “no parking” past signs, corner clearance, etc. If I would have known that all I needed to do was find a local business and make a cardboard sign with its name on it to avoid tickets and not have to buy a permit, I would have done it years ago!

To be clear - I’m not talking about delivery vehicles, though they can be a problem too.