You jump though the hoops to make your order, make an account, choose your pizza, and enter your credit card info.
You click submit. Nothing happens. Did the order go through? Do you call to find out? Wait and hope? Order from someone else? In the future you'll have an answer (or 4 different deliveries because you went somewhere else 3 separate times until you found an accessible website).
What if you didn't have another option? Should we prevent the blind from eating pizza?