At some point your lack of tracking itself becomes a data point. When someone shows up to a website who is a complete data ghost, the site has to figure out how to react to that. I could see companies saying, "well, if someone has no record, there's two possibilities. Either one, they're chronically homeless and are living completely off the grid. Or two, they're somehow who goes to great lengths to hide their tracks. In the former case, we can ignore them when setting our prices, as they can't afford our product anyway. In the latter case, we can charge them the maximum, as wealthy people can more afford to care about their privacy, and the person avoiding the tracking will probably assume we're actually giving them the better deal."

I imagine most such systems would be set up so that by default the maximum price is charged, and it's only lowered if tracking data is available to suggest a lower price is more likely to create a more profitable sale.