The main reason that it still exists today, at least to my knowledge, is new morphs. Most BP morphs were wild caught or CH babies that got sold to US breeders for tons of money.

The most popular story that comes to mind for me is the first pinstripe ball, it was purchased by Brian Barczyk, without seeing it first, for like almost $30k. The importer told him it was completely different than anything he'd ever seen, so Brian bought it, proved it genetic, and was able to build most of his facility and company with one very expensive imported BP. So every pinstripe related morph in the world is related to that one snake. At least that's what I've heard over the years, I've tried looking for any real evidence of the story on the web, but the only evidence is BHB being listed as the original producer on WOB and some videos on youtube that tell bits of the story.