I've worked with all these guys, and the most plausible reason I observed boiled down to anti-counterfeiting: in their view, data sheets are a map to creating r

I've worked with all these guys, and the most plausible reason I observed boiled down to anti-counterfeiting: in their view, data sheets are a map to creating register- and pin-compatible clone parts. While the knockoff market is very real, it always seemed far-fetched that NDAing data sheets would be that much of a protection. You would think a sophisticated shop has enough relationships to get the sheets via a close contact, friendly supplier, etc..