Can I make people approve each registration?
No, and the setting that looks like approval is not enforced. A registration lands on the list as soon as the form is submitted. Your filtering happens in the form, the door and the tidy-up, not behind a gate.
Do you block bots or disposable email addresses?
There is no captcha, no bot detection and no verification service here. Disposable addresses arrive on the list like any other. Seat limits bound the damage; reading the names yourself is the filter.
Does removing someone tell them?
No notification goes out when you delete a name, so junk entries disappear quietly. The statuses you maintain โ registered, attended, waitlisted, cancelled, no-show โ are for your own record.
Will a waitlist fill up with the same junk?
It can, and it is worth pruning there too. The difference is that a waitlist overflow is not the number you plan the room against, so the pressure on it is lower.
Is a big list better than a clean one?
For anything you have to serve, no. A believable count of forty beats an inflated two hundred, and the reminders you send afterwards go to people who were real enough to sign up.