Speaking of Don Steinbach, I just found another article about the hotel buying trips of the mid-70s, this one focusing on Eric Lange, Don Steinbach, and John Rumierz. It was reprinted from the Baltimore Sun in the Sports Collectors Digest of 10/31/75, and a quick Google search revealed that the story originally ran in the Sun on September 22, 1975. (Below my scan of the story from SCD, I've given a link to a picture of the three men from the Sun's online archives, which presumably accompanied the story.)
What's interesting about this story is that it quotes two unnamed "local collectors" who derisively referred to the three men as "dealers", and complained about how the dealers were ruining the hobby by "forcing prices up to ridiculous levels". I would dispute that claim, because people like Lange, Steinbach, and Rumierz weren't forcing prices anywhere -- they were providing liquidity and bringing a lot more cards into the organized hobby, as jsq notes, and were riding the beginning of a wave of increased demand due largely to demographic factors, as baby boomers entered their prime earning years and sought to recapture their youth through sports memorabilia.
Link to picture of Lange, Steinbach, and Rumierz:
http://baltimoresun.imagefortress.co...sults_index=23