The main question is it safe? If it's safe and the ammonia serves a purpose and cooks out of the food and prevents food illness then it's serving a purpose. I don't see any side effects mentioned and I'm sure billions of pounds of this meat have been consumed.
And at least we have a choice. I'm sure that if it's safe that the millions of people that are starving around the world would love to have this meat (treated or untreated). They don't have a choice, they have nothing to eat at all...
Some shocking studies have concluded that the US wastes half of it's food, which is ridiculous considering that would probably feed most if not all of the starving people in the world (link below)
http://www.foodnavigator-usa.com/Financial-Industry/US-wastes-half-its-food