My opinion is that this photo is neither photoshopped nor an 'old' photo at all.
Rather it is a modern 'staged' photograph with the colors converted to sepia to make it appear old. Possibly taken on the set of some film production using actors dressed in 'old time' garb.
Actually, ice tended to follow the railroads, so there were places in the Old West where they did have ice. But you're still right about this being 'shopped, since very few cowboys drank champagne. Most preferred a dry merlot, slightly chilled.
