It's an outhouse used for storage it looked like. But what interested me was the saffron robe lying discarded in that box...and with that black arrow on the box pointing up and giving importance to it.
I had never seen a saffron robe lying around and unworn like this in all the time I have been to Thailand. Ones i've seen have always been worn devoutly by the monks.
The tiffin carrier trays are portable food carriers, and sometimes a monk will take one of these with him on a pilgrimage to another temple or religious site. He can be offered food and money by villagers he passes along the way as alms, in return for his blessings...