I think it just depends on what you want out of your vacations. If you want to spend time doing non-RV trips, then it doesn't make the RV "obsolete", it just means you have varied interests in vacations.
For many of us who still work, traveling 2500 miles by RV to get to a destination isn't viable, so we use the airlines and hotels to enjoy going someplace further away. However, the RV allows us to spend long weekends away from home without breaking the bank. For the cost of a night at a "nice hotel", I can get an entire long weekend at a campground within 4 hours of home.
As for "camping" or "traveling", I think an RV works well for both (dependent upon other factors) or one or the other. I don't think it's an all or nothing deal.
So tell your wife to relax. You can plan non-RV trips even if you have an RV. Or you can break up an RV trip with a nice night or two in a nice hotel.