In general, I think the problem breaks down this way:

1) Humans respond in intuitive, predictable ways to graphics, particularly with a greater emphasis on emotional response. (As opposed to an analytical response.)

2) All information sources have bias, and any marketing competence on the part of the infographic creator will tend to subconsciously amplify the bias of the graphic's creator.

3) Combining the creator's bias with the infographic's tendency to more easily invoke emotional responses over analytical ones results in a reaction more couched in that emotion than in logic.

IIRC, USA Today was criticized for this, decades ago.

[edited to fix concatenation of numbers to a single line.)