Trespass is a crime.
And does not fall under this discussion.
The discussion is: a right to self defense was recognized by the founders, it exists whether or not you want it to.
Property owners who have a business known to attract criminal attacks take on the responsibility if they short sightedly deny the right of defense because they are busy wringing their hands over “eeeevil guns”.
Therefore, damages death and destruction caused by their demands of disarmament are on them.
So, you seem to be saying if a number of gang bangers show up on a store owners property, armed, he cannot order them to leave?