Hi Russ and thanks for getting in touch!
Great question. The short answer is that The Events Calendar does have the ability to take free and paid reservations through any of our ticketing add-ons.
The longer answer is that those are the e-commerce and reservation systems that we currently integrate with. In other words, I am not aware of The Events Calendar integrating with WP eStore and it is possible the two will not play well together–I have to admit that I am unfamiliar with WP eStore, so I don’t have a great deal of confidence in telling you one way or the other.
That said, there is another (free) extension to The Events Calendar called Event Rocket and this does include the ability to take RSVPs for events.
Sorry I don’t have more of a concrete answer for you, but does this at least help? Please let me know and I’d be happy to answer any of other questions as best I can. 🙂
Cheers!
Geoff