On the whole, it has been an impressive year for Beyond Meat and Impossible Foods, the leading makers of plant-based meat. Restaurant sales of meat alternatives have risen 268 percent. Beyond Meat’s share price has soared since the company went public in May. Impossible Foods’ partnership with Burger King has increased foot traffic at some of the chain’s locations. And several other major chains — including Carl’s Jr., the Cheesecake Factory, Little Caesars and Qdoba — have introduced meatless meat products.

But among big chains, there are also plenty of naysayers.

After The Information reported in May that Arby’s was in talks with Impossible Foods, the fast-food company publicly disavowed plant-based burgers, and cast itself as the guardian of “real meats.”

In June, Shake Shack’s chief executive, Randy Garutti , said on CNBC that he had no plans to introduce a plant-based product. “Shake Shack was built on doing classic things better than other people did them,” he said. “So let’s watch a little bit.”

And Taco Bell , which is introducing a new vegetarian menu this fall, has also chosen to stay on the sidelines.