People who live by “the norm” can often feel justified in their position simply because this is the view most commonly held. When a large portion of society adopts a particular position, it is more difficult to challenge. Trying to persuade someone to become vegan is trying to convince someone to change the way they make all their social decisions, which can leave them open to ridicule and even hostilities.
When a person already holds an alternative point of view, they are more resilient in the face of ridicule and can stand for what they believe. If these people adopt a vegan lifestyle, it will significantly challenge the status quo. Once this happens more people will feel comfortable changing their stance on veganism.
“Those who stand for nothing, fall for anything.”
When a person uses logic to determine their best course of action, they will ultimately become vegan.