Contrary to popular belief the purpose of church is to further educate your spirit and renew your faith in God. When people worshipped in temples that had bare earth for a floor and stone for benches they did not bear silk dresses or kahki slacks. Gathering for worship should be a casual encounter and not a date with Christ. I call upon Christians to keep their fancy attire locked in the closet and attend each Sunday with their everyday clothing (if it is a suit, so be it!).
My reasoning for my feelings? A touch of a sense of biggotry with a dash of vanity. We're taught to be humble and love one another. There are those that do not have the benefit of a Sunday outfit and we should not exclude anyone by an unspoken expectation of one. A change of dress code would do us all a little good as church has become too much of a social function instead of a spritual one.