That's just my guess- no snake has ever personally confided that to me-But I don't recall a BP ever drinking from a water spray to their face- whereas my rat snakes happily will. I've kept many kinds of snakes- they're not the same, & it keeps things interesting. Also, a water spray is usually pretty cool, & BPs like to be warmer than most of my snakes do. So it might be the chill factor also?