Incident on the M62.

After having a particularly knackering week back on the treadmill after a four week absence I decided to take the family to Bridlington for the day.
Everything started off normally, get the kids in the car, get them out again for a final wee. Get the wife in the car, get her out again.....you get the picture!
We set off, up to Ainley top onto the motorway, past Brighouse, past Leeds, past the M1 interchange, past Pontefract when all of a sudden a big bang from the car, lots of juddering noises, steering all over the place. I managed to pull over to the hard shoulder expecting I'd had a blowout on one of my tyres but on inspection they looked fine. I was just about to phone the AA when a police patrol car pulled up behind me. A very nice and pleasant WPC offered to get the AA for me and they arrived within 20mins. Mark the patrolman, towed us off the motorway to get a better look at the car which he diagnosed as having a rear wheelbearing gone. He then towed us all back home, a distance off about 25 miles and left the car at the garage.
Now I know I like to have a moan now and then but these two people were stars today, even my kids were playing breakdowns with their bikes when we got home!
Question- Why is it that I feel more hungry when I leave a Macdonalds restaurant than before I went in? And why do I feel that I've been ripped off when I come out?