Today’s blog post from top executives at Cloudflare blasting Amazon Web Services for the “egregious” fees it charges customers who move their data out of AWS’ servers raises an interesting question. Could the most fertile ground for pursuing antitrust action against Amazon lie in its cloud business, not the ecommerce business that gets all the attention from business media and politicians?

Amazon’s outrageously high “egress” fees, as they’re known, are no secret. We’ve written about them in the past and last year’s House Judiciary Committee report into competition in digital markets dug into the subject as well. That report noted that these fees are one of “several common techniques” used by cloud providers to “lock in customers.” Cloudflare’s blog, written by CEO Matthew Prince and a senior Cloudflare executive named Nitin Rao, note that Amazon doesn’t charge for data transferred into its network, only for transfers out. Their conclusion is that AWS’ rationale is “locking customers into the cloud and making it prohibitively expensive to get customer data back out.”