An ex-neighbour of mine, Bert Prescott, was a man who really loved tractors. He collected them, he drove them around town, he collected books on tractors, he went to tractor shows, he loved anything to do with tractors.
One day, at a tractor show, he got hit by a tractor and was severely injured. After months in the hospital and rehab, he finally got his life back on track, but now he hated tractors.
He sold every tractor he owned and vowed never to have anything to do with tractors ever again.
One day he was walking past a burning house with people trapped inside. There was so much smoke that the fire-fighters couldn't get in.
So Bert walked up to the house and with a huge breath, sucked all the smoke out, long enough for the fire-fighters to enter and save the people.
Afterwards, a fireman said to him "Bert, that was amazing! How did you do it?"

He replied, "I'm an ex-tractor fan."