Why stand on a mount?

Epic Ride checks confer the ability to stand on a mount. What mechanical benefit does this confer? The only description given in the SRD is:

“This allows the character to stand on his or her mount’s back even during movement or combat. The character takes no penalties to actions while doing so.”

but I am unaware of anything that is actually gained from doing this. Is this a blunder? A recent and related answer from KRyan found nothing.