Microsoft CEO Satya Nadella and Volkswagen CEO Herbert Diess (not pictured) attend a session during their visit to Volkswagen Digital Lab in Berlin on Feb. 27, 2019.

In the cloud wars, Microsoft has been able to win big business from retailers, largely because companies like Walmart, Kroger, Gap and Target are opting not to write big checks to rival Amazon.

The more Amazon grows, the more that calculation could start working its way into other industries — like automotive.

In a recent interview with CNBC, Volkswagen's Heiko Hüttel, who runs the company's connected car division, said the carmaker chose Microsoft Azure late last year for its "Automotive Cloud" project after considering Amazon Web Services.

Hüttel said he's not worried about Amazon building competitive cars, but suggested that there are other things the company is doing in connectivity that could seep into Volkswagen's market. Amazon was recently seen hauling cargo with self-driving truck technology from start-up Embark.

"If I take a look at all the competitors out there, you see they have capabilities in disrupting you at the customer interface," Hüttel said. "Then you have to carefully choose who is really getting down into the car, where you open up a lot of data to these people, and then you have to carefully choose with whom you are doing business."

Microsoft likes to tout the merits of its cloud technology, but the company is fully aware that taking on AWS, which has a commanding lead in the cloud infrastructure market, isn't just about offering the best services. Under CEO Satya Nadella, Microsoft is taking a much different tactic from the days when it was viewed as a potentially risky partner.

"We're not going to turn around and compete with our customers," said Julia White, corporate vice president at Microsoft, at a Goldman Sachs tech conference in San Francisco last month.