People are entitled to their opinions. They're not entitled to make up crap that they then proclaim as 'fact' upon which they then base their 'opinion'. These actions are known as a straw man. It's normally the chosen tool of those whom have NFI, or have such a weak position that it's the only way they can distract from said weak position.
You can normally pick the quality of people as to how they utilise this tool. In fact, it's quite a handy example of intellectual and emotional maturity.