If you are far enough off level to damage the refrigerator, you will be far enough off to feel uncomfortable walikng around inside or sleeping (unless unlevel makes you head high) and you won't be able to use a griddle on the stove because grease or eggs will run over the side. Water may not all flow to the drain in the shower pan.
I know a lot of RVers have been conditioned to obsess about level, with dire warnings about the fridge, because they can't relate the requirements of the refrigerator to real life.
Most places I'm using the RV, parking sites are level enough, and if not, usually 2 iches or less of boards and blocks under one or two wheels will get me there. Automatic levelers don't necessarily do a better job achieving "level" but they make the job easier.
For most of the people who consider leveling jacks a "must have" in a motorhome, the factor driving that choice is not leveling, rather it is stability. They want the solid support of jacks under the house so that it does not bounce around when people move, or sway when strong gusty winds blow. You will get these movements in a RV that is supported on its tires and suspension. particularly when people are heavy or move heavily. On something as lightly built as a C, you may still feel people moviing heavily when sitting on jacks. Somethimes the only real solution to a big person stomping around is to get a 30,000 to 40,000 pound motorhome.