Most people don't do any research before they start vaccinating their children. It is really sad.
Some people also don't realise that improvements in hygiene can also cut down the risk of communicable diseases and that some of the improvement in those was a result of that, not just the shots.
But I guess some people also think that forcing me to do something is acceptable; all for my own good , of course (since they somehow know better than me what that is)