Maybe I had a unique experience, but when I was in grad school (chemical engineering) we exclusively used LaTeX for thesis work. The journals we worked with also required it, if I recall correctly.
You should count your lucky stars if you were able to submit in LaTeX format. It's obviously the best format for journals but they've all stampeded to Word.
Like I said, maybe I was just really lucky, but I never had to deal with Word for grad school. Of course, this was also 9 years ago, so maybe a lot has changed since then. Do journals in the engineering/sciences world really not accept LaTeX anymore?