I;ve seen a lot more funnier lines on here.
To the OP, Boston's a pretty diverse town, so chances are there'll be a good number of Arabs, as well as restuarants, etc. Although I'm not Arab, for Malokin, and other ignorant ppl out there, 99% of the Arabs u see in this country don't wear turbans. The guy you saw was most likely of Indian origin. A certain group of Indians, called Sikhs wear turbans.