You could be right, but it could also be that it was common knowledge that he was anti-gun because he never was shy of sharing his opinion, and it's very common

You could be right, but it could also be that it was common knowledge that he was anti-gun because he never was shy of sharing his opinion, and it's very common for the same truckers to do the same routes repeatedly. I don't think there's enough evidence either way in this anecdote to make any reasonable conclusions.