Hey Sean,
Thanks for reaching out!
To be absolutely clear about this: The Events Calendar has no bearing on payment methods, SSL, or eCommerce on your site whatsoever.
There are no payment methods “integrated with” The Events Calendar or even our ticketing add-ons at all.
This is all handled by eCommerce plugins themselves. So, if you have WooCommerce on your site for example, than it is WooCommerce itself that integrates with PayPal and such. The Events Calendar just handles events; that is it.
I hope this clarification helps a bit!
— George