Because if you think about it... it does kind of look like a palm tree; just stockier.
Mom in hemp shop: Hey, Janet, come here, do you think I should buy this purse?
Me, baffled and shocked: What? You can't buy that purse. That has a MARIJAUAN LEAF on it!
Mom, more baffled than me: Really?
Me: Yes. That's pot. That's cannabis.
Mom: Oh... I thought it was a Stocky Palm tree.
Me: Not quite.