You have it backwards. Horses aren't forbidden, you can still use them on the road. The horror, you can even still walk by foot on the road (near the side).

Some wealthy parties nowadays try to convince certain players to forbid cash.

[edit: disclaimer: of course depending on states law, horses/cars/pedestrians/trains/what-ever are forbidden or allowed on certain autobahn/freeway, railroad, subway, etc. The point was about forbidding cash for the sake of forbidding cash, just to track all your money movement, to be transparent. As a consequence you have to be very careful and loose your freedom. That would be like going back to Soviet Russia or similar times, were the trust is gone.]