The answer to this puzzle is in the language used to pose the question. In reality, there is no "missing" $1. 3 x 9 is indeed 27 (a bit of linguistic misdirection), and the bell boy does indeed have $2, but adding them together has nothing to do with solving the problem, it just adds to the confusion (and makes the puzzle what it is).
Here's the real breakdown: The hotel has $25, the bell boy has $2, and each of the men have $1. So, 25+2+1+1+1=30, nothing missing.