Our 2009 Jayco Greyhawk motorhome came with a full size spare. It also came with a lug wrench, but no jack. I wouldn't want to travel without a spare tire in any vehicle.
If you have Roadside Assistance, check with them to find out what they will cover. In our region, AAA RV would only cover mounting my spare tire. They wouldn't cover removing the failed tire from the rim and putting a new tire on the rim. I was told by a fellow RVer, that CoachNet wouldn't cover that either and they had to pay the mobile tire guy $100 to mount his spare tire onto the rim.
Our spare tire came mounted on the rear bumper. I took it off and put it under the bed since tire mount interfered with our hitch mounted bike rack.
-Michael