On the wall in my kitchen there currently hangs my favorite nativity.
A clearly exhausted Mary is lying down in the hay herself, cradling the baby Jesus along side her, while Joseph takes care of them.
There was no room for them at the inn. From across time, we scorn the inkeepers who would not spare a bit of space for the mother of the Son of God. We do not suppose they knew the import of the event, but we are still aghast that there was so little kindness shown to someone in such need. It is the opposite of what the little babe would later teach and practice throughout his life.
But perhaps it was for the best.
Consider the bed at the inn. The mattress would probably have been stuffed with hay itself. There is a good possibility that this hay would not have been changed for several days. Weeks even, and perhaps months in a poorly kept inn. Hay does have a tendancy to mold, especially in a warm, moist environment such as the sleeping place of a sweating, drunk traveler. Neither would the bedding had been cleaned and changed for several days.
The hay in the stall, on the other hand, would have been dry and fresh. Under those circumstances, it was most likely as sterile an environment as could be had in those days.
So before we wonder at the humble beginnings of our Lord, perhaps we can imagine instead a God directing them to a safer place for Mary to birth His Son.