That you haven't met someone who can't take vaccines is not a reason to dismiss them. Intuitively, such people may prefer to stay in self-quarantine to protect themselves, making you even less likely to encounter such a person during a pandemic.

However, getting vaccinated should also help reduce the transmission of the disease to people who haven't yet had a chance to get a vaccination even though they could; the pandemic will end faster than if you let it run its natural course.