Everybody does it.
When someone on basenotes says "do not blind buy" what they really mean is "it is sensible advice to advise others not to blind buy, I however trust my judgement and am willing to take some risks so I will blind buy myself."
I think if you are a fragrance collector and buy and sell fragrances a lot anyway it's fairly easy to shift on a bottle that you don't want and also you are more comfortable with spending money and taking the risks anyway. It's part of the hobby.
Blind buying is more risky for a newbie getting in to the hobby as it is easy to get carried away early on and discouraged if you blow money on something you don't like, eg the keen 18 year old who discovers Luca Turin's book and basenotes and decides to blind buy Habit Rouge.