I flew out of RIC during the "mass exodus" Sunday right before Christmas (all the soldiers from Fort Lee heading home for a couple of weeks) and TSA personnel were making everyone throw away their MREs or eat them before proceeding through the checkpoint. I think they had peanut butter and a fruit cup in them, both of which are too liquid/gel-like to pass through security these days.

TSA at RIC are usually pretty level-headed and follow TSA SOP well, so I imagine that the liquid/gel ban applies to MREs just like it does to civilian food.