What if the game you purchased accepted nickels from the factory, but you want to put it on route and collect quarters to match other games that you may have in various locations?
You have to add extra switches or change adjustments to accept the new denomination.
If you wish to just do a one-for-one coin exchange, you just change out the coin mech, but if you want to provide some extra value for higher denominations, you have to add additional circuitry. This gets more complex in Bally bingos, since you have multiple systems that are already working together in the start circuit.
