PA has some weird animal laws... very loose in some species that really could use restrictions, very restricted in some species that don't really need it. I believe the concern with hedgehogs was that they are a potential carrier of hoof and mouth disease - though if you read more on the matter it seems the laws are, as usual with exotics laws, based less in real risk than in fear mongering.
To be clear, gliders are legal in PA with a permit. There are few states in which they are 100% illegal. I'm not certain why however. I can only assume based on other exotics laws that they either a. fall under some kind of general blanket restriction simply because they are exotics, b. have some real or imagined potential to become invasive or c. carry some kind of pathogen that probably virtually no one and no thing has ever contracted from them, but lawmakers responded to public fears or pressures from agriculture.
To be clear, gliders are legal in PA with a permit. There are few states in which they are 100% illegal. I'm not certain why however. I can only assume based on other exotics laws that they either a. fall under some kind of general blanket restriction simply because they are exotics, b. have some real or imagined potential to become invasive or c. carry some kind of pathogen that probably virtually no one and no thing has ever contracted from them, but lawmakers responded to public fears or pressures from agriculture.