Actually low mileage should be more of a concern to look at carefully that it has been 'sitting' parked up to the rims in dirt as opposed to them spinnin back the mileage! :B
Then there are RV'ers that only take a few trips a year. The mileage you are talking about is not unusual for the occasional RV'er.
Keep in mind not everyone is full timing it in an RV. Most only get 'one week' vacation a year to go on a long trip. The rest are short janunts on the weekends.
So many RV'ers keep detailed logs of their treasured trips and are more than happy to share them with you.