My wife wears pants. Even to Church. There, I said it. I never really gave it a second thought, at least beyond noting it to be the case, that is. You see, she hates skirts and dresses, and does not own any, period. She dislikes shorts as well, though she owns a few pair which she wears at the beach or pool.
I always thought that it was unusual, but kind of nice at the same time. You see, I generally dislike the things too. Skirts and dresses always seemed to me to be a bit impractical and awkward. I may be wrong, never having worn them, but it just seems that way to me. Now I will tell you that she always dresses modestly and neatly and is the most faithful, conservative Catholic I have ever known. She not only brought me back into the Church when I was lost and had drifted away, she brought in her best friend, as well. She is truly devoted to our faith.
I never put any other meaning to it at all - her attire, that is. But, apparently, there are a lot of people in the world of traditional minded Catholics who find it offensive. To all of you out there, I apologize in advance, because I just don't get it. I can see getting upset about sloth and slothful appearance (they go hand-in-hand IMHO). That bothers me even outside of church - it upsets me tremendously in Church. I find it offensive as hell to see people go to communion in ragged boat shoes, beat up shorts, and tee shirts with God knows what kind of things them (my personal favorite was "I was a pig at _____ Barbeque").
I have often said that in the pusuit of the truth-in-advertising that people so dressed should have t-shirts that say "I don't give a ____". In fact, maybe have them say it both front and rear, so that those of us who DO give a _____ know to avoid them at all costs. Kind of like the old testament rules about lepers having to say "unclean, unclean" whenver someone would approach. Man, now that I think about it, that's a great idea!!! But I digress...
I like to be casual, sure, as does my wife, but not inappropriately slovenly-looking. I don't think that nice, decent casual dress clothes - khaki pants, nice blouse, maybe a jacket on top of that, is inappropriate dress for church. So please don't confuse slack and casual, or criticize the latter because you are disgusted by the former.