I'm not sure I'd blame his weirdness and attitude on the Church, specifically, though. I think you'll find that any uber religious person who tries to break into the corporate world will act similarly. Unless things have changed, it was actually mission rules to shine his shoes regularly and to dress as well as he could.

Also, I've known cheapskates who are LDS and cheapskates who aren't who all act the same way about spending money. Really, what you can take from this interview is that the kid is probably a moron. I say that because, if he has made it to the point of interviewing for a job that requires that kind of an appearance and he still doesn't understand how things work out there in the real world, he is either very dense or willfully doesn't want to learn/conform. Either way, he'll be trouble for you.

Now, with all of that said, you might want to consider the fact that you are more obsessed with fine clothing than the average American male so maybe he's not as weird as you think compared to "normal" people and just seems weird relative to your views.