A user can land your page from multiple referrers (or the same) more than once and some search engines including Google will hide the referrer information so th

A user can land your page from multiple referrers (or the same) more than once and some search engines including Google will hide the referrer information so the calculation will be off IMO. The regulations are not strict if you're not identifying the individual people from your visitor/user data. If you're collecting user event data into your servers and can prove that you're using the data just for the analytics purposes (i.e. providing a better user experience to your users) there is nothing you can afraid of using cookies. That may not be the case for third party analytics providers though because if you're using Google Analytics, you're responsible from how Google are using your customer data.