jw411 makes some fine points about fuel and diversions.
Now a days, I can see doing that (US domestic) and getting to BDL (that's in connecticut for you foreign folks) and having the crew go out of duty time sitting it out in BDL (which has an excellent on airport hotel if you get stuck there and have the money...but I digress).
So, in the fuel equation must add the crew going off duty at an airport without a new crew available for a day or two. Putting passengers up at a hotel can get expensive too, though modern times has cheap airlines letting passengers sleep on a plane with no water or operating toilets.
Don't get me wrong, JW411 has some fine points. And sitting in a holding pattern in rotten weather watching the fuel go down down down is not fun at all.