The people who fly those are diehards of the 1st order. They cost a fortune, especially the jets.
Too bad they didn't have the B-52; that's a huge model and it actually does have 8 jet engines just like the real thing.
We had friends in CA who built a Spruce Goose from the actual Hughes plans, the same people also built a flying wing. I was present for both maiden flights.
Here is the Spruce Goose on static display - you can see how large it is with me standing behind it
and this was pics take of the maiden flight testing at Prado Dam, California
My husband won a lot of trophies with this plane - it was a replica of the British AAA plane, we were able to make contact with the original pilot through the museum in San Diego, he and George wrote back and forth and he even sent us a piece of fabric from his uniform which I used to make the uniform for the pilot for this model
This was the last large model George built before we moved to Arizona and he retired - as AC said it is a VERY expensive hobby...