In a public setting, the only people who should be able to hear a video are the people who agreed to watch it.

If you are the only one watching something you need to use headphones so only you can hear it.

If you are showing it to a friend then you use the speakers with low volume so two people seated closely can hear it but someone at the next table cannot.

Remember the people working there serving the food and the others eating there did not ask to watch the video and should not need to hear it because they cannot or do not want to watch it with you.