money's money, he's now realised that, english fans being ridiculously into anything english, losing didn't effect how he was treated in any way at all. So he can get paid a crap load of cash, lose and still be beloved in his home town, boxers are in it for the money like most people in most jobs. Why wouldn't he take the fight?
he can't win, unless Mayweather gets into absolutely awful shape and doesn't train in the slightest, even then they were a miles apart in terms of fighting ability, it will take a untrained lazy and uncaring Mayweather for Hatton to win.