If you would like to encourage a priority group to reduce their meat intake and increase consumption of plant-based foods, consider the use of default settings. At restaurants or in school cafeterias where there is a menu (whether digital or not), vegetarian options can be listed first instead of last.
In one Swedish field study,
"...when the meat option was listed first and the vegetarian choice was only listed as an alternative at the bottom of the menu, around two percent of customers ordered vegetarian. When the vegetarian option came first with meat listed as the alternative, around 20 percent of patrons ordered vegetarian."
An 18% increase in consumption of vegetarian food is significant. This is a form of choice architecture that is easy to implement and does not infringe on the priority group's freedom by limiting options, as banning certain kinds of meat would do.
To read more about choice architecture and default settings in the context of sustainable eating behaviours, please see the Behavioral Scientist article here.