Ever since Louis Meyer celebrated his 1936 Indianapolis 500 victory with a swig of buttermilk, winners of “racing’s greatest spectacle” have followed in his footsteps. But if PETA had its way, winners would celebrate with vegan soy milk instead.

Claiming that “cow’s milk is for calves, not for drivers or other humans,” the animal rights group has purchased a billboard near Indianapolis Motor Speedway denouncing one of the most iconic traditions in sports.

PETA billboard decries Indy 500 milk tradition. https://t.co/KwcQC25Y3k pic.twitter.com/C7ph3UeUOT

— NBC4 Columbus (@nbc4i) May 24, 2016

“Since toasting with a swig of bovine breast milk is, well, rather milk toast, we’re encouraging fans to raise a glass to the races and to moms with a more appropriate beverage: Gatorade, soy milk, or, perhaps, the true celebration drink—champagne,” PETA said in a blog post on Tuesday.

The 100th Indianapolis 500 takes place on Sunday.