If Wile E. Coyote and Pepé Le Pew met up at the bar, they'd probably have a lot to talk about, like the thrill of the chase, or how Acme products are kinda bogus. Then they'd cheers and Wile E.'s shot glass would inevitably explode in his face.
"Oh hey guys… this? Why, it's just my delicious sodium- and calorie-free J&S seltzer that doesn't suspiciously smell like beer in the slightest! Anyone up for some seltzer pong?!"
In case anyone had any doubts as to why you showed up, just stare at them blankly, abruptly point to the cup, grab their shirt by the collar, chug contents, don't break eye contact.