Not a lawyer.
From the argument, it seems that the violation of the conditions in itself is not trespassing. Trespassing is staying after the conditions were violated. Since the person was promptly removed, it is very hard to argue that they trespassed.
No criteria. Everyone gets the same exact stipend, whether they have 0$ to their name or 1 billion dollars. Its not necessary for UBI to not have criteria, but it should, because: