gruzie,. that is nice that they were so nice to you, although at our McDonalds the staff are expected to remember to pack straw and napkins, so I don't consider that " extra service" in any way. I do think they were being very nice to you though, helping with the language barrier and all, and as teens who wouldn't be excited with a tip.. but I hope that now they don't expect it every time they serve an American in a rush, or else they may be dissapointed. You see it was a nice gesture, but sometimes gestures can create false expectations.
It was nice what they did though, and you know, they were probaly nice to you , because of how you acted, not because they expected a tip. Its a weird cycle,,we want to reward people, but I also am wary of teaching kids to expect immediate gratification for doing their jobs( as opposed to waiting till pay day, when they are employed in a non tip job)

Pay and working conditions continue to go up in most western countries, but I can't say service levels have improved much ,, can you?

When I was at a conference in New Zealand I dined with an Australian and a Dane and the Australian insisted on tipping, despite all the guidebooks vehemently denouncing tipping in NZ!

I've aimed for 10% in Europe, or as the custom dictates (rounding up, a Euro here or there).