If you create a segment with a smart rule, Marketing Automation constantly updates the list so contacts always meet your conditions. Our conditions utilize both data we receive from your booking software (i.e. which contacts have purchased your 10 Class Pack) as well as data from Marketing Automation (i.e. which contacts filled out a form).
If you'd like to view a list of frequent visitors without memberships, for example, create a segment specifically for frequent visitors without memberships. The list will always stay up-to-date, so you can refer to it whenever you'd like.