I haven´t that experiences with angelfish as you describe - can you please give some background data?
Sincerely Lasse
I don't really have any empirical data to cite and obviously it would depend on the species, but my guess would be 1/2 to 1/3 that are collected ever actually make it into a home aquarium.
I've never worked for a wholesaler and admittedly it's been about a decade since I worked in the industry at all, so my opinion on this may be outdated...