Meh, the ice cream machine is a different thing. I haven't figured out fully how it benefits McD's, I suspect there's little profit margin on ice cream, but having the machine at all still brings (hopeful) people in who buy something else. A bait-and-switch.

McD's uses the same machine as many other places, but they have the temp variance much tighter, so much tighter that after the daily cleaning cycle, it takes hours to get back to temp.

Then (and this is probably what you're referring to), if the machine has a code, the franchise is required by contract to use the repair service that comes with the machine lease.

There's an indedependent dev who wrote a code reader/reset tool for the machines, and McD's isn't happy about it.

I'm not clear how doing the maintenence this way benefits McD's, unless they own the servicing company, and it doesn't appear that they do.

In the end, it means McD's will often not actually have ice cream available. But these are franchises, so it would hurt the franchise most directly. Seems there'd be a potential legal issue here, if it could be proven.