Complicating the situation, though, are input costs that aren't rising uniformly and the fierce competition among processed food makers that could result in additional promotions. Because of this, the impact for restaurants is "not as clear cut this time around," said another Bernstein analyst Sara Senatore.
RBC Capital Markets analyst David Palmer expects a modest acceleration in food-at-home inflation, which he views as a "modest positive for the fast food industry and a slight negative for casual dining," which has bigger input costs and less pricing power due to higher check averages.
"If it turns out to be a real turn in food inflation that's sustainable, it's something that would be a real positive for the fast food industry because there's a roughly 75 percent correlation of fast food industry same-store sales to at-home food inflation," Palmer said.
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But isn't a restaurant meal price still much more expensive than a home-cooked one?
Often, but price isn't the only factor customers consider. Senatore stressed that while the prices are still not comparable, "the point is in periods of inflation you see that gap narrow a bit."
"Accounting for the cost of the time spent preparing a meal at home narrows the gap substantially and helps explains why seemingly modest changes in pricing can change how the 'share of stomach' is allocated," wrote Bernstein analysts.
Not everyone buys the argument.
Steve West, a restaurant analyst at ITG Investment Research, said he doesn't think the divergence will result in "much change."