As I have answered previously, the number alone may be sufficient to identify the matching data set. If you have 100 records, and the number of tickets varies between 1 and 5, the averagte number of records with 5 tickets is 20. If you have a gaussian distribution, only one or two records will match the 5 tickets. This makes the data set personal data.
As I also have answered earlier, you may use a single-opt-in question together with either different opt-in questions or together with
panelUpdate() to collect and store the email adress separatedly, and add include additional data. The separation, however, may be less strict (depending on the opt-in settings) compared to the separatedly collected email contact data.
The address entries will, for example, have a database ID that increases monotonously and allows to reconstruct the order in which the email addresses were collected. From your point of view, the data will still be as anonymous as the separately collected contact data.