If I had to hypothesize, I would say that there is some perception by outsiders of the study of engineering that makes it seem valuable. I once heard a chem engineering student say (in chemistry class, I took two semesters of chemistry for fun) "why would I want to be a chemistry major? you never get to blow anything up." I'm not implying that this young man would be interested in terrorism (I don't think so), but I just want to point out that his humor and point of view are completely foreign to me, and but we are both ostensibly students of science. It seems like many of the engineering students I know like science because its "awesome", whereas many of the science students I know like science because they think it is important and interesting.
What is more, there is a very, very large number of engineers who are also very deeply religious in America. Which is also interesting.
I would really love to read more research into this, if anyone has any ideas.
PS, no offense to anyone in particular if you are an engineering student. I think you understand that I'm not making statements about all engineers. I almost went that path myself, and actually can't remember why I decided to stick with computer science.