Tutoring Zone Lottery

A tutor delivers a short lecture on the concept of expected value. His first example uses a deck of cards. He does the same for the guessing penalty for standardized tests and for playing the lottery. The tutor ends the video with a remark: The lottery is just a tax on people who are bad at math.

What is the meaning of his remark? In the case of lottery players, why do you think people continue to play despite negative expected value?