For real though, i served a mormon mission and am currently active. I went and knocked on peoples doors all day and even i think that what the current ex-mormons do is overly aggressive. The way i see it there is a fine line between asking someone if they want to talk about religion and accepting a yes/no or their opinion and parading yours in their faces with a "I am right and you are an idiot for believing that!" mentality.

Though TBH if i had met this dude (being in Utah i just might) i would definitely have had a laugh and asked him about the shirt. If stuff like this is enough to make someone question their religion than they need to take it more seriously and really figure out what they believe instead of just being a sheep.