"We will never sell your data or use it to target ads" is disingenuous. A statement of extreme simplicity that hides the truth. Like when the government says "we won't wiretap phones", when they know people hardly rely on phone calls mainly anymore.
When companies collaborate they can exchange data, but not necessarily with a price tag attached to it. It suffices it's part of a broader, mutually-beneficial interchange, no need to 'sell' specific data chunks per se.
By the same token, when a company shows a customer information they think he'd like or potentially be interested in (based on browsing data), that facilitation, that "grease", can draw the customer closer to an experience where the product is present, even if never named as such, or only much later. Or when multiple products are present, advertisers could "pool" their fees according to each product's relative presence.
Just as we understand the difference between product and service, we must understand that between service and 'prepping' or 'honing' a new or future customer. I don't think new advertising is going to be specifically for a brand but rather an involving experience. Just as the data you give, never clear what's going to happen to it after you give it, or how its strings are going to be pulled to drag you in.
You don't know it, CloudFlare doesn't know it, nobody knows it. The data alchemists work behind the scenes and are always a step ahead. A new marketing for the 21st century.