Source: The NPD Group/National Eating Trends
These diners have driven a "dramatic increase in home delivery and takeout," Allen noted. Chipotle, in particular, has seen an uptick in takeout orders, growing to about two-thirds of orders, up from half eight years ago, according to its latest earnings call.
Still, Allen thinks grocery stores have been faster to adapt with more single-serve options.
"Restaurant chains absolutely need to pay more attention to this as a segment, and the smart ones are and have already made changes to their menus' and restaurants' designs and training," he said.
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Industry watchers say they're seeing a bigger emphasis on restaurants' bar sections, more two-person tables and communal tables, faster wait times and smaller menu items.
"On the menu development side, it is a trend toward faster," said John Gordon, principal at Pacific Management Consulting Group, in a phone interview. "Single diners aren't going to generally spend two hours. The turnover will be faster. Because the turnover is faster, the actual entree or food itself is either smaller, lower priced or more individualized."