Picture it: You hop into a robot taxi to visit your dentist. A video — make that a hologram — pops up, suggesting you try a new mouthwash. Later, as a car drives you to dinner with friends, a commercial plays in the vehicle, offering half-price drinks at a nearby bar. As you play a game on the car’s built-in screen, more ads bombard you with suggestions related to your current route — and where you went yesterday and the day before.

The good news is that your rides are free.

Once fleets of autonomous taxis start ferrying people around, many prognosticators expect we’ll have in-car ads that subsidize the rides. That conjures images of a dystopia like Steven Spielberg’s “Minority Report,” in which Tom Cruise strolls through a mall lined with screens that address him by name to tout various products.

“We are going to have advertising-supported free transportation,” said Tony Seba, founder and principal of think tank Rethink X. “You’ll get on board; it will start offering you goods and services. Whether it’s like ‘Minority Report’ or not will depend on privacy laws.”

It’s not just ads that will subsidize robot rides, he said, but various services. They include familiar ones such as streaming videos, music, games or virtual reality plus some new business models.

“Retail itself will change,” Seba predicted. Bars, restaurants, music clubs and theaters might offer a free ride to and from their venues to anyone within a 10-mile radius. Mobile vendors may give free rides to customers who buy food and drink en route.

“Advertising is likely to change into something less in your face, throwing products everywhere you look, to something more like branded entertainment,” said David Pal, managing partner of Los Angeles’ Ads on Top, which links advertisers to networks of digital screens in various places, including malls, kiosks and atop ride-hailing cars.

Google, whose sister company Waymo is a pioneer of self-driving research, already offers numerous digital products from its search engine to Gmail and photo storage for free, underwriting them with targeted ads. Industry analysts say Waymo may well turn to a similar business model.

Apple, which is working on autonomous vehicles, offers CarPlay connectivity and entertainment software, something that observers say could be part of future robot cars.

The startups that are using today’s cars for advertising are the first wave of this trend.

“We’re definitely the precursor to what you can expect from self-driving fleets,” said Zoli Honig, co-founder of Santa Monica’s WaiveCar, which offers free rentals of cars bedecked with ads. “There’s no reason for autonomous vehicles to be owned by individuals, they’ll be owned by fleet operators.”

“We will be able to provide an omnipresent channel for entertainment whether on the bus shelter, sidewalk or cars,” said Pal from Ads on Top. “We’ll deliver content as people move throughout the world at all these different touch points.”

New York’s Cargo, which equips Uber and Lyft drivers’ cars with a box of snacks and sundries for sale, is an early example of in-car commerce.

“Our belief is that ride-share services in the short term and autonomous vehicles in the long run cannot exist without value-added services,” said Jeff Cripe, Cargo’s CEO. “There will be a demand for more comfort and more productivity in vehicles. We’ll be positioned to lead the charge in developing the next passenger experience for autonomous vehicles.”

Vugo, a Minnesota startup that makes software for video screens that show content and ads in ride-hailing vehicles, sees its mission as making most trips free in the future, according to co-founder James Bellefeuille.

“I believe there’s a chance to make short trips in autonomous vehicles advertising subsidized,” he said. Referring to concern about the dystopia of all those ads, he said: “As someone who comes from humble roots, I don’t think it’s a nightmare; I think it’s a dream.”