Disagree on not going to BK/Wendy's. The "deals" game becomes a habit, switching costs are basically zero, people start to comparison shop each app for the best deal (like shopping for air travel). It's a bit of work because there is no single consolidator but it only takes a few seconds to scan each apps offers.
At this point, being a fast food chain that doesnt have an app with deals is probably not viable - but I am very skeptical it generates any loyalty.
