GigaPower by AT&T, the company’s 1 gigabit-per-second service, was introduced in 2013 in Austin, Texas — and this week it rolled out in Kansas City, Missouri. While customers can enjoy ultrafast fiber-optic Internet access for $70 per month, AT&T also tracks their online activities. Those who prefer to keep their browsing habits private can pay an additional $29 a month. Since opting out of sharing such data is typically offered free of charge, some are questioning whether AT&T’s model will discourage people from doing so.

The additional charge “seems like a huge penalty intended to normalize the practice” of tracking customer data, suggested Stanford University computer scientist Jonathan Mayer.

However, AT&T “characterized the GigaPower privacy option not as a charge to people who opted out of tracking but as a discount to those who didn’t,” reports The Wall Street Journal.

“We can offer a lower price to customers participating in AT&T Internet Preferences because advertisers will pay us for the opportunity to deliver relevant advertising and offers tailored to our customer’s interests,” she said.

Companies including Facebook and Google offer consumers free service if they are willing to share personal data, but it is unusual for a company to charge extra to protect customer privacy.

“AT&T and Verizon opened new lines of business selling their customers’ mobile browsing histories to advertisers,” notes WSJ. “The companies stored hidden, undeletable tracking codes on customers’ phones. But customers protested because there was no way to opt out of these so-called super-cookies.”

As a result, AT&T said it would shutter its smartphone-tracking program. Meanwhile, its new service helps advertisers target consumers by tracking search terms, page visits and clicked links — despite individuals’ ad-blocking and cookie-disabling efforts.