Virtually every food, including fruits, veggies, grains, etc., has protein. Your co-workers are victims of propaganda, spun by the Cattlemen's Association. They've been mentally trained into believing that only blood-food can supply protein. Your co-workers are being manipulated. You might tell them so.
"There is more wisdom in the song of a bird, than in the speech of a philosopher...." -Oahspe
"The thing is, you cannot judge a race. Any man who judges by the group is a pea-wit. You take men one at a time." -Buster Kilrain, The Killer Angels -Michael Shaara
"Anyone who doesn't believe in miracles isn't a realist." -Billy Wilder