What would Jesus do? Maybe be like the rest of the immigrants - come in, expect everything for doing nothing and then try and change everything to suit his wants.
What's the harm/goodwill... ? Just guessing you don't keep your door open for strangers to just waltz in as they wish. Once turns into twice and soon can easily become a magnet for others (word gets out).
Mary and Joseph were not refugees or homeless. They were going to Joseph's hometown per the census decree. Joseph was a skilled craftsman and would have had a decent to better than average income. I would lock my barn and be alert.
would cause some concern for me. Mary and Joseph had the Inn keepers permission to sleep in the manger, this person/persons did not.
Motion sensor lights, stay armed, and you may want to notify the police just so they are aware.