Depends on the party composition but there are a few cantrips that easily get cast over 20 times per day outside combat.
Shillelagh, Mage Hand, and Guidance are generally assumed to cast constantly to keep their duration refreshed without the player needing to mention casting it.
Dancing Lights, Create Bonfire, Mending, Message, Minor Illusion, Druidcraft, Prestidigitation, Elementalism, Blade Ward, Resistance all have cases where a player might spam it repeatedly outside combat