Hi Raymond,
Great question, though I am afraid that Event Tickets Plus only supports collecting information on a per-ticket basis. In other words, the fields you set up to collect attendee information will be displayed for each ticket that is added.
One possible workaround you might consider is to use something like Gravity Forms to add a form to an event that asks the questions you want answered on a one-time basis. I realize that would be a little odd insofar as the information submitted would then not be attached to the event, but in a separate area of WordPress. Still, it might be worth considering.
Does this help answer your question? Please let me know!
Cheers!
Geoff