Payouts from records were also quite meager unless you were already a well-known act.

Music labels contracts have always been exploitative, they usually require the band to pay back costs like studio time, producer, mix/master engineers, marketing, before getting their cut of royalties in sales, for artists without clout the royalties share would be 75/25 to the label (or worse), more famous acts can get a 50/50 split, again after recouping the costs.

As any passion industry it is extremely exploitative, as much as people like to hate on streaming platforms nowadays the music labels have been the most evil aspect of it all for 70+ years and they managed to lurk in the shadows without attracting a lot of flak.