Most people pay with their debit card and it's just become easier to have the machine to handle those purchases for those few individuals who still use cash it will be a little bit of an inconvenience to have the extra step put in to the ordering system. But in General Tso line will be non-existent and flow much better for the restaurant.
You're better off going into McDs in person and ask for a manager to ask that. This is going to have more patrons than managers.
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