Galleries should capture emails

Most other photography CRMs (even photo booth CRMs) allows galleries to capture emails from people viewing the gallery. Can we have it where we can change the gallery settings to allow emails to be captured before the gallery is accessed. For example - if I sponsor an event and the event host shares the gallery with the attendees, I would like to be able to capture the emails upon viewing the gallery. I know sprout studio does this as I was with them before unscripted.