I think some (key: not a lot or all) people are interested, but they don't want to come off as strange. For example, if I had not seen my relative w/ Aveda products I would not have known that she gets the same joy taking care of her hair as I do. I would just assume that she just kept her hair on point like a lot of women who are not necessarily into haircare...I hope what I'm saying makes sense.
Another thing, I, as a black women, am hesitant to compliment people w/ long, healthy hair, because A) sometimes it really was a great weave or B) some people have had long hair all of their lives and thus seem a little jaded when you compliment them...
ETA: This is from IRL experiences not LHCF. I must say that the BSL or longer ladies here are some of the most humble individuals I have encountered.