A significant fraction of the population has a religious or moral objection to eating lard. A smaller but still substantial part of the population objects to tallow based on vegetarianism or the terrible environmental impact of cattle raising.

That would make sense for a chain that otherwise served vegetarians. But does McD's even have a single item that is vegetarian?

I googled it, some breakfast items (egg mcmuffin, panckages) and apple pie.

It's probably just a money saving feature. I'm already old (34) and I've only ever eaten the veggie oil McD's fries.

McDonald's fries are a special case, because, as some vegetarians discovered after years of being misled by their "cooked in 100% vegetable oil" claims, they're already flavored with beef tallow.

Then don’t eat it.

I didn't really know about this until I listend to this great podcast episode about the whole fries story. Can highly recommend it: http://revisionisthistory.com/episodes/19-mcdonalds-broke-my...

(The rest of Revisionist History is also great!)

Just about everyone's chips (fries) and crisps (chips!) are a shadow of their former selves. When I was a kid just about everyone made their chips and crisps in beef dripping or lard. Now not even all supermarkets carry it, all bags of crisps use veggie oil, and the only place we get decent chips is at home.

Yet beef consumption has risen hugely over the same timescales.

The same thing has ruined potato chips. All the good chip brands in this country now have limited regional distribution at best. The tyranny of Frito-Lay has totally ruined the chip industry.