There's an interesting piece at Slate.com: The Crappiest Invention of All Time - Why the auto-flushing toilet must die. By Nick Schulz:
He includes this bit:
"Hands-free toilets and faucets are certainly smarter now than when they first came on the market. Pete DeMarco [an engineer and expert] told me that when automatic fixtures first got popular in the early 1990s, they had difficulty detecting dark colors, which tended to absorb the laser light instead of reflecting it back to the sensor. DeMarco remembers washing his hands in O'Hare Airport next to an African-American gentleman. DeMarco's faucet worked; the black man's didn't. The black guy then went to DeMarco's faucet, which he had just seen working seconds before; it didn't work. This time DeMarco spoke up, telling him to turn his hands palm side up. The faucet worked."
While Schulz tosses this off as human interest, it might really represent how some "discrimination" works. I suggest what happened is that the engineers who initially designed the faucet tested it out rather thoroughly. They probably used themselves as guinea pigs. And the faucet worked, so it was put on the market. But guess what, it just so happens that none of the engineers were dark skinned. Result: something that would appear to many like discrimination. And in a way it is. No one intended the result, but it was the by-product of the fact that blacks haven't been well represented in engineering. I'd suggest this sort of interrelationship is quite common, if you look hard.