saw this movie one time when i was knee high to a grasshopper in late 80s-early 90's - but a huge monster grizzly bear terrorizes a summer community. im pretty sure the thing rampaged through people at a festival/carnival close to a pier for the boss fight. The bear was friggin huge and i remember the move being more than bloody. was not the movie "grizzly".
I'd say Prophecy, except there's no festival carnival scene. You might be thinking that because of the scene in the one camp though, and the final confrontation is in a cabin next to a lake...
Here's the ending to help you check.