Then you're causing harm to someone through deception, the harm is what's criminalized. You can lie to people all day, but if you use deception to steal money directly, physically harm someone, or otherwise cause monetary loss, that's when criminal (or civil) cases can be brought.
If I say snickers has no peanuts and you think peanuts are icky, nobody is going to jail. If I say snickers has no peanuts and you are deathly allergic, I may. The lie itself isn't illegal, if it was, I expect my door kicked in here shortly: Snickers contains no peanuts.
Well, my door is still intact and no criminal charges have been filed.
If lying counted as fraud, literally every politician (as well as every other human) would be in jail currently.