I think when you’re on a free trial that information is really useful to help you decide what plan you would need if/when you do start a subscription with us. Using that as an indicator of how many pageviews you expect can help you get a good idea of what capacity you would need, and budget accordingly.
As Ethan said, if a site is already established and has started to consistently go over its pageview limits we would work with them to figure out what options are available. 