MORE.....
Don't underdress. This is God's House. If you don't know what's appropriate (say from the website), ASK (it's not hard to do). Call or email. They'll tell you if it's fine if you come in your PJ's or a worn tank top, shorts and floopies.... Good general rule, actually: ASK.
Take no offense if the answer isn't the one you wanted. It's not your family. And yeah, there's more than one church available - some church has everyone in PJ's. There are even churches for nudists (Just don't assume the church you are visiting is one of them).
.(The Josiah Dot)
This is something I'd actually say is potentially a bad thing.
When churches decide to adopt dress codes it creates a more exclusive huddle. People who don't fit in become excluded and the church runs the risk of becoming little more than a frightfully middle class talking shop. What happens if the local vagrant or "lady of the night" hears something about some guy named Jesus and wants to go to church to find out more? What happens if someone who can't afford a fancy outfit wants to come and worship God?
It's not your family but at the same time it's not their family either - it's God's family. What James had to say about giving the rich man the finest seat in the house and directing the poor man to sit on the floor in the corner seems to apply here.
On another forum a guy insisted that new people should adhere to the norms set by the church, and that the church should provide the funding if they were unable to do so. He literally believed that if a homeless person turned up and wanted to worship there, they would buy the homeless person a smart outfit so they could stick to the church's dress code. How the homeless person was supposed to maintain and clean their nice new outfit was unclear, as was the value of some nice clothes to a person who would probably find it more useful to have access to hot food and a shower.
I wouldn't tell people they shouldn't wear a suit to church - some people are naturally comfortable in a suit and consider it appropriate to dress up. At the same time I would be very concerned if a minimum dress standard over and above basic decency were imposed because it does create a sense of "you're not good enough to worship with us". If a "lady of the night" were to attend church I'd hope she could be offered something to cover herself but at the same time would hope she wouldn't be shown the door because she wasn't appropriately dressed - Jesus never told anyone who sought him to go away and return once they had themselves sorted out.
I would agree with the part about showing up in your PJs - unless that really is the absolute best you can rustle up I'd say that's just being lazy for the sake of being lazy, but then I'd be inclined to say that going out and about in your PJs isn't really appropriate.