Parks are doing it because it gives them an easy way to market an old ride as new. As much as I hate saying this Galactica was successful because most people were under the impression it was a new roller coaster. Even a lot of Merlin's employees didn't realise it was just Air with a few headsets added until they went to visit.
The VR fad will only end when VR becomes commen place. I remember in the 90s when simulators were built up as the next big thing. Eventually the gimmick wore off, partly because rides like Spider-Man started appearing, perfectly merging old and new technology to create some of our best rides today. This is why I'm far more fascinated by AR over VR.