If the garage were good to collect the car, fix it & refund you then id say no to compensation.
Unless other damage was caused to the car as a result of the wheel falling off......
IMO that just shows that this particular garage accepts its mistakes and puts them right with no quibbles. Good Garage??? It could be you had an apprentice work on your car and they didnt check his work, MAYBE?? But i understand its not a nice thing when the wheel flies off!