Because they hold the reins!
Because people marvel at what's holding it up. And they wish it would fall.
A: Siamese twins.
The Rolling Stones say "Hey! You! Get off of my cloud!" And a Scottsman says "Hey McLeod, get of me ewe!"
Only the tip baby, I promise!
Jockey straps.
They take a gallop poll!
Looks like rein dear"