It will take less of an RV to tow a Jeep four down than it will to also tow the extra 1,500 - 2,000# of trailer. If your Jeep is really built up, you may want to put it on a trailer, but otherwise, most people don't bother. They tow fine on all four. The trailer is just one more thing to maintain, license, and find someplace to put when you're in an RV park. You can usually pay more for a large pull thru slot - buy why? And if you don't have room for it at your house, it's another storage bill also.
If you don't use a trailer, a Class C will tow it four down just fine.
Bill
Nodwell RN110 out moose hunting. 4-53 Detroit, Clark 5 spd, 40" wide tracks, 10:00x20 tires, 16,000# capacity, 22,000# weight. You know the mud is getting deep when it's coming in the doors.