Hello,
I believe the additional fields may be your best bet if the person submitting the event will not always be the organizer. With a customization, you could hide/remove these fields from the front end of the single event page so that they are not visible to the public on the published event. We are a bit limited in the amount of support that we can provide for customizations, but if you get stuck removing the fields, please let me know – I’ll be happy to point you in the right direction!
If contact fields for anonymous users is something that you would like to see added in the future, please let us know over in our Feature Ideas Forum. This is what we use to gauge user interest in new features and help guide future development.
I’m sorry I don’t have a better solution for you here, but please let me know if you have any questions.
Thanks,
Jennifer