The customer is implying that it is obvious between a barbie and a hot wheels which is gendered for boys. So instead of saying which toy they want, they are expecting the employee to identify which is for boys. It’s a subtle way of reinforcing gender binary and societal expectations of what is “appropriate” for children to want to play with.

Oh yeah, you think your knob collection is better than theirs?

Agree with you but OP did not write the article title