Seventy years of sprawling suburban development makes cars the most practical way for most people in the U.S. to get around, but actually owning that car may become optional.

Particularly in urban areas, car sharing is steadily growing as an alternative to ownership--and apparently at a much faster rate than many previously thought.

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Roughly 18 percent of Americans have used a car-sharing service, WardsAuto columnist John McElroy said during a panel at the 2014 SAE Convergence automotive electronics conference.

He also said that 60 percent of Americans are aware of Zipcar and ride-sharing service Uber, despite both companies and the services they peddle being relatively new.

On the other hand, McElroy said only 40 percent of Americans are aware of Kia--a claim that may bruise a few egos at the Korean carmaker.

Zipcar will add the 2012 Ford Focus to its college car-sharing locations

Zipcar will add the 2012 Ford Focus to its college car-sharing locations

The comparison between car-sharing service and carmaker isn't just for shock value, as the programs have already been shown to have an impact on new-car sales.

A report released earlier this year by consulting firm Alix Partners found that car sharing could eliminate 1.2 million sales by 2021 if it remains as popular is it is now.

RELATED: Carsharing Eats Into New-Car Sales, According To Study

Automakers are also getting involved in car-sharing themselves.

Mercedes-Benz parent Daimler supports Car2Go, which operates a mixed fleet of gasoline and electric Smart Fortwo minicars in several European and U.S. cities.

Perennial Mercedes rival BMW operates its own DriveNow service in Europe as well as San Francisco employing ActiveE electric cars.

Those ActiveEs were previously used in the pilot program that laid the groundwork for the current BMW i3 electric city car.


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