Hi Decli,
Yes, you are correct: both plugins are separate and the front-end submission form is included in Community Events. I do want to note that PRO is not required to run Community Events–that will work right out of the box with the free version of The Events Calendar.
Also, just a heads up that $149 is the price for the Business-level license. A Personal license would be sufficient for a single client and that is $89.
Does this help answer your question? Please let me know.
Thanks,
Geoff