Speaking as part of a panel discussion Monday at the Fortune Most Powerful Women Next Gen Summit in Laguna Niguel, Calif., Rachel Bhattacharya, the chief growth officer of Maven Gig, General Motors’ (GM) new dedicated mobility service, said that the biggest users of the service are Baby Boomers and recent retirees.

Maven Gig, which launched this past May, gives occasional gig economy workers a way to easily gain access to a vehicle for short stints like grocery shopping and delivery services. “They just want to own less stuff,” Bhattacharya told her audience.

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That aligns with a recent University of Michigan study that showed that the proportion of Baby Boomers with driver’s licenses has declined, down 3 percentage points since 2008.

Surabhi Gupta, the director of engineering of Homes at Airbnb, agreed. “The largest portion of hosts are not Millennials,” she said.

It’s not just about affordability on the part of the renter, said Bhattacharya, but also on the part of the owner. “You can afford a nicer car if you rent it out, and you can afford a nicer place if you put it on Airbnb,” she said.

And there is plenty of money to be made, according to online residential real estate site Trulia, which reports that extra rooms are an opportunity to supplement income and offset cost-of-living increases by as much as $14,000 a year.