Well, you're not the only one but I think we're definitely in the minority! Personally, I always hit a minor bump from 70 to 80 and end up with a abundance of jobs in the seventies. It's probably more from thinking "It's nearly done, no rush to entirely finish it right away" than any real difference in levelling, though. I just wish there was an option to begin all jobs at level 1, or at least no higher than 30, considering how quickly they level.