You're right when rentals aren't parked level for the Fridge, because they either don't know or they don't care about one else their property. The same rule applies to batteries, they are usually ruined after the first trip, because they drain them down till nothing lite anymore.
Recommend to keep your refer within the manufacturers specifications.
2014 Ram 1500 CrewCab 4x4 5.7 Hemi 3.92 Rear and Air Lift 1000
2005 Jayco Jay Feather LGT - 29Y GVWR-7000 lbs.
Dexter Axle Lift 4-9/16" - installed with sub-frame.
Pro Series 1200 lbs. WDH with Double Sway Bar.
Champion 3100/2800 watt Inverter/Generator-Onboard Solar Power