So I have been thinking on this for a little while. I am completely against the idea that to be a proper man, we must dress like they did 100 years ago. I hate the entire notion of a tie. My suit stays in the closet with the exception of most respectable events(pretty much weddings and funerals, may there be many of the former; few of the later).
The question that keeps coming into my mind is why did they dress up more back then. You saw them in nice pants for even the most mundane of tasks. Going out, you saw a nice jacket in the least.
I can only honestly come up with two possible answers.
1) There was more respect in self and others to be your best and look your best.
2) There just weren't the options for different types of clothing, it wasn't economically feasable to get them to the masses affordably, and therefor you got what little was offered.
I would heavily come down on the second option. The reason you see the guys dressed like that is that was all the really had. Seriously, for the most part they looked the same. Then added with cost of the clothes, you would take a lot more pride in how you wore them and cared for them.
I would willingly bet that if they had our options for variety of styles mixed with the widespread affordability, those ol' timey pictures would be radically different.
That, or I am just rationallizing for hating to get dressed up.