Well, I'll put my two cents in on this topic.
My sister, my cousin and myself all work for McDonald's, and all at different stores.
The one my cousin works at is a bit messy, the service is slow and the employees are treated okay, there's nothing too bad about it.
My sister's store had very fast service, a higher rate of workplace injuries and the store is spotless.
Lastly, the one I work at is pretty dodgy - although service is fast, the store's often a mess and most of the managers have never heard the words "Workplace safety." There are several sleazy employees (both male and female) who harass junior staff, and even when customers get abusivewe have to keep smiling at them. (I've put in a request fo a transfer.)
My sister's been working there for three years and is a trainee manager. She's looking fo work elsewhere and as soon as they hear she's worked for McDonald's they want to hire her, because it's got a reputation for being very good training.
My point is, it can be good to work for the old golden arches, but no two stores are alike in terms of how the employees are treated. It's not always a crappy job - if it is, I suggest you transfer to another store before you quit, unless you're certain that it's the job you hate, not how you're treated.