Neither Haver nor the studio had anything to do with the arrest. You're right. I just re-read that segment in Haver's book and it it was exactly as you described. The fan who blew the whistle on the collector may have won the battle to get "Lose That Long Face" back (The version seen in the Radio City Music Hall premiere was Haver's reconstruction from alternate takes) but probably forced more collectors underground for fear of losing their collections.
Until the video age movie studios did not want individuals owning prints of their films. Older titles that were in the PD they could not control and a few small companies struck deals to issue films in 16mm and 8mm for libraries and home buyers. (Blackhawk used to sell Laurel and Hardy's classic comedies this way. The library I worked at in High School had many of these films on 16mm form Blackhawk.) But aside from these issues, the only way one could get a complete print of a film was to steal it.
Collectors did manage to save many titles that studios lost or discarded, but they had to keep a low profile.
I have always loved A STAR IS BORN and for years wondered why two key songs that were on the soundtrack album were never shown on TV. Then came the announcement of the restored version in 1983. There were complaints that it wasn't 100% restored, but when you watch it now there is only 5-6 minutes that are covered by stills and few minutes of soundtrack that were cut because they lacked stills to make the scene work. The bulk of the film is there and it plays beautifully.
I shudder to think of the mess Andrew Lloyd Webber plans to make of this one.
Cast albums are NOT "soundtracks."
Live theatre does not use a "soundtrack." If it did, it wouldn't be live theatre!
I host a weekly one-hour radio program featuring cast album selections as well as songs by cabaret, jazz and theatre artists. The program, FRONT ROW CENTRE is heard Sundays 9 to 10 am and also Saturdays from 8 to 9 am (eastern times) on www.proudfm.com