The cowboys and prostitutes go back to their drinks, well-accustomed to this sort of random violence, as the man nonchalantly twirls his pistol and says: "Guess he couldn't read my poker face."
A typical western saloon, moments before everyone in the room shot each other.
A hundred years of Westerns have taught us that this is how you lived and died in the Wild West. The quicker draw lived to gun-fight another day. It was essentially a roving single elimination rock, paper, scissors tournament that didn't end until you were dead.
But in Reality...
How many murders do you suppose these old western towns saw a year? Let's say the bloodiest, gun-slingingest of the famous cattle towns with the cowboys doing quick-draws at high noon every other day. A hundred? More?
How about five? That was the most murders any old-west town saw in any one year. Ever. Most towns averaged about 1.5 murders a year, and not all of those were shooting. You were way more likely to be murdered in Baltimore in 2008 than you were in Tombstone in 1881, the year of the famous gunfight at the OK Corral (body count: three) and the town's most violent year ever.