Ooh a really fat fee! Whoever managed to was the miner who mined that, kindly return the 250 btc to the address indicated in my profile. The rest you may keep for your honesty lel.

Things like this do happen in the bitcoin ecosystem every now and then. Some are lucky to have theirs returned and others aren't.
#1 human error (unlikely)
#2 some script messed up
#3 just a miner having fun fusing inputs
1 is still possible. Drunk dude sent it? Who knows?
2 is somewhat probable, considering that most automated payments are run via scripts.
3 is, uhmm. Who would do that, really?