It's on YouTube instead.
"Super Bowl 50 audiences will be missing out on comedy, sex appeal, and the lifesaving message that vegan meals can help clear clogged-up carnivores and get their blood pumping again," says PETA Senior Vice President Lisa Lange in a statement. "PETA's edgy but crowd-pleasing TV spot shows that vegans may have a banana in their pajama pocket, just to snack on later, but they're also really pleased to see you."
PETA submitted a Super Bowl ad in 2009, "Veggie Love," that was rejected by NBC. It' not clear whether this one was ever actually submitted to CBS. But we'd bet some executives examined it closely anyhow.