It depends. If I know I'll make an order only once, calling phone is probably easier. If that's a pizza, and say I have expectation that I might be ordering same pizza every week or every month, then ordering through website is easier, since you can save your credit card information there instead of repeating it on the phone every time. But even for one-time orders it is good to have an accessible site, since what I mentioned above - I would waste my time if the web site is not accessible. I assume if they had put a notice on their web site saying that it is not accessible for screenreaders - please call this number instead - that would be already a better solution rather than just an inaccessible web site.