Always freaks me out a bit how quickly people will claim stuff that is not theirs just because they can.
I think it was the intention of the OP for it to be claimed. He likely wanted to draw attention to the passphraise of the brainwallet.
Fair enough assumptions to be made but none of it was stipulated.
It is kind of like just putting your wallet with $5 in it on a table in a crowded room, should you expect it to be immediately mobbed by everyone?