Rubber

Nick and his wife where waiting at the bus stop with John, his spouse and John's nine children.
At last the bus drew up, packed with poeple.
The two women, and the nine children managed to get on, but the men where left behind and had to walk.
After trotting along the road for an hour, Nick's walking stick got on John's nerves with its continual tapping.
- Why don't you put a rubber on that stick! John complained.
Nick snapped back :
- If you'd put a rubber on your stick, we'd have got on that blasted bus.