Technically, it is a little bit more involved than what you describe, but essentially you are correct.
Here is part of an answer that I posted to a prior post, which applies to your questions:
MacroMedia releasing a CFMX product for Mac OS X:
MM people will tell you that it is a simple matter to make CFMX work on Mac OS X. That, in itself, does not justify them releasing and supporting a product. They need to make a profit and a return on their investment of resources. MM does not make any money on the Developer version -- it's free. They make their money selling CFMX for installation on production Web servers.
By most measures, Apple is a late entry into the general-purpose Web Server market -- there is not a large install base of Mac Servers that MM Marketing can target.
That said, there is a lot of interest in CFMX on Mac OS X -- inside and outside of MM.
I, for one, believe that a business case can be made to release a supported Developer version for OS X. The theory being that it would attract new CF Developers, and that New CF Developers will drive the sales of CF Server software (regardless of the fact that they are developing on OS X and deploying on some other platform).
My opinion is that a offering free Developer version for Mac OS X, is a relatively inexpensive way for MM, to gage the market interest and potential -- small interest, little lost -- great interest -- maybe there is an opportunity that needs to be addressed.
I hope you enjoy the port!