I think the popularity of their artists (i.e. Hancock, Turrentine, especially Silver) was their best investment. Those records sold well years ago and are still selling.
Same for Prestige. Despite what we all say about Concord ripping through the old Fantasy catalogue, a hell of a lot is still available - I just counted sixteen Gene Ammons CDs on their site; nine by Mose Allison; and at least two dozen by Jaws. And even Ernestine Allen's one album for TruSound is still in the catalogue. If it's still there nine years after Concord bought the company, you can be sure there's enough sales in it for Concord. Same for Mildred Anderson, the one of her two Bluesville albums featuring Jaws.
MG