When dining out or receiving any other type of service, be aware of both giving compliments and criticism. People are quick to complain when something goes wrong, but sometimes neglect to compliment truly great service.
If you have a complaint, share it calmly and quietly with the person with whom you have the issue. If a resolution can’t be made, go to a manager,etc.
Likewise, compliment your server or service provider on a job well done, and if you feel so inclined, mention it to their superior as well. Complimenting others will help you feel good and be a welcome change for people who are used to hearing people’s complaints.