If the ingredients have "yeast extract, autolyzed yeast, yeast food or yeast nutrient" among others, you're consuming MSG - even hydrolyzed protein.

Lots of Chinese restaurants advertise "No MSG."
Plenty of it in Japanese food. Ever hear of Ajinomoto?
Plenty of it in all the packaged crap on the non-Asian aisles in FaTass USA.

Yet only people seem to get MSG headaches after cheap American-Cantonese food.

Once again, it is probably the 5+ grams of sodium consumed at the place.