Totally agree. Logical solution, and everyone is happy. I used to be a hostess/waitress in college at a restaurant that had 24 hour service, and a smoking section. We had the people who bought one cup of coffee (free refills) and sat at a table smoking for 5 hours a night. If you were lucky, they tipped 25 cents for the whole table. UGH. Yes, minimum order for an hour of free wifi seems fair to me!
I used to live in a college town about 5 years ago where you couldn’t even get into the local Starbucks because people had been sitting there all day doing research for their master’s thesis. I stopped going there (I did my research at home, and I went there to have a cup of good coffee and see other human beings) and so did many other non-students.
However, as wifi has become more available, things seem to have settled down a bit. I don’t see the plague of students quite to the extent that I used to, and Starbucks has actually improved its lackluster menu, so maybe there are more paying guests turning up now.