I'd never heard of it until I saw your post. After a quick look at the RoverPass web site it seems like an Xpedia/Priceline tool for RV campgrounds. Seems like it could be useful, particularly during high use periods such as holidays or in high demand areas.
If you or anyone out there is using the tool please post your comments.
Here area a couple of snips from the RoverPass web site.
Lucius and Danielle
1992 29' Excella Classic / 2010 Interstate
2005 Chevrolet Suburban K2500 8.1L
2018 GMC Sierra K1500 SLT, 6.2L, Max Trailering
Got a cooped-up feeling, gotta get out of town, got those Airstream campin' blues...