

Special characters is just one case to cover. If the user says they want “an elephant-sized drink” what does that mean to your system? At least that is relevant to size. Now imagine complete nonsense input like the joke you responded to (“-1 beers” or “a lizard”). SQL injection isn’t the only risk with handling inputs. The person who ordered 18,000 waters didn’t do a SQL injection attack.
I didn’t expect republicans to interrupt their own masturbatory moment of silence. Anyway, I would’ve been tempted to rip the loudest, nastiest fart I could muster, even at the risk of shitting my pants.