It depends on the location. There are some that a huge portion of their business comes from the drive through, and of course ones in shopping malls for example not that much.

When I use to visit McDonalds I always thought it was pretty funny that there was one that would have ten or twelve cars in the drive up window (actually I could come up with a few of them) while there was nobody at all inside. I could park, walk in order, and leave and still be six or seven cars ahead.

In some areas, up to 70% of the sales come from the window, which is why in some of those places they have dual windows, car service to keep the cars moving, etc.

It's a huge part of some of the locations business.