There are a lot of trash players at casinos. That is a fact. People go to casinos to gamble and those same people see poker as gambling. They're easy pickings.
The games arent harder or softer its exactly the same. The only reason why people say online is harder is because you play a bigger volumne and run into the truth quicker of being good or bad.
playing live you can win for a lot longer becsuse of the volumne so you can mislead yourself of being better than what you really are.