Vegatarian V. Ego Defense Mechanism

On Friday Alex spoke about a billboard supporting meat eating and then asked why people were so threatened by vegetarianism. I replied by saying, "People come up with those ignorant sayings because they feel the need to rudely over justify their meat eating so that they can protect their egos." In further inspection of the topic, I found that this situation, does in fact, resembles a certain type of ego defense mechanism. In psychology courses they only teach you the ten Freudian ego defense mechanisms, yet there are others. I won't go into detail about all of the others but I will mention that they are typically divided into three categories: primitive; less primitive, more mature; and mature defense mechanisms.
Among the primitive defense mechanisms is "acting out." The man and the billboard would fall underneath this category. Acting out is preforming an action (puting up a meat eating billboard) instead of feeling the related emotion. People who are defensive have a hard time facing their shortcomings. Instead of excepting other's opinions they fight fire with fire.
Some individuals, feel threatened by vegetarianism because they are at risk for feeling guilty for something that they have been taught is okay their whole lives. An individual does not want to admit that they are a bad person for advocating the death and torture of another being for their own earthly use. In order to refrain from such feelings, they go to the extreme with excuses such as: "That's why God put them here," "PETA is just exaggerating, the animals don't really go through all that suffering," and, "Everybody else eats meat, so it's okay." By instantly dismissing the ethical aspects of meat-eating with excuses, the feelings of guilt are not felt.

Question: Is there a psychological aspect to eating meat and testing on animals? Perhaps cynical?