This is not an unusual occurrence. If anything it has increased the foot track in the McDonald's that do offer free wifi. The unnatural occurrence was when I opened my laptop case and pulled out a yellow legal pad and pen. An very audible gasp could be heard. My mind quickly recalled a commercial from a few years back with the people in a bakery (not sure) all checking out and swiping credit cards as they went through the checkout. Well, one person gets to the checkout and pays with cash. Instantly, everything stops. The people look at this form of payment as outdated. A few seconds later all resumes.
I'm sure you have seen far crazier things than what I just relayed, but I had to laugh at the looks i received from my fellow fast food patrons.