Here is the worst old-time rule I could find:
Up until the year 1886 - a jockey could not dismount after a race unless he first asked permission to dismount from the stewards.
This made it easy to stiff a superior horse - all you do is go out and win the race at odds of 1/10 - and the jockey hops off before he asks permission - horse gets DQ'd - bettors become outraged.
