Cant believe your wanting an inner tube back ,,
I remember years ago I used to give three lads a lift home from work every night in the car, I never asked for petrol money, then one night we ran out of petrol (the petrol gauge did not work) and I had no money, so reluctantly one of them gave me £2 so I walked a mile to the get petrol.
The next day as soon as I walked in he was there asking for the £2 he lent me !!!!!!! so much as to say they all had to walk home from that day on , ,, some people are in the words of Jim Royle "a right tight get"