Each restaurant is a franchise, owned by an investers. McDonald's Corp will just push your complaint back down to them. Call during the day and get the top manager, get his/her name and store number. Ask for the area's manager and his/her phone number. Call them with your complaints.
Don't eat there
Find a phone # on the McDonald's website, a contact email or a way to leave a comment. It's difficult on purpose so the corporation cannot receive bad reviews. Most people just give up. If you can manage to get in touch with someone, you will probably get a coupon for something free, and the franchise owner will be informed of your complaint.
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