Yes. If you have a link to a site that has the ability or even another link to another place where you can buy something, Apple will block publishing of your app. They pulled this on us earlier this year after three years of publishing with no problems. All we had was a link to our support site, which had a link to our main site (where you could buy a subscription), the latter we had to remove or they refused. In fact, if we even try to give users materials on subscription details or talk about (not even providing a link) how to find those details, Apple blocks it. They need to get smashed with the antitrust bat hard.