Do we need educational online platforms?

I have tried the various classroom/conferencing programs from WebEx to Moodle.
All the technical bugs may not be out, but they were at least adequate.  The problem was I felt constrained.  I had to fit my material into their format.  I was limited in what I could do.  And in the back of my mind, there is the feeling.  "This does not belong to me.  Remember Ning."

I own Moodle, but I use Elluminate.  

An idea that I have had for a while now, needs some outside evaluation.  Let talk about it.

Cloud Conferencing.  Do not use any platform but take advantage of free and open source applications.  

I start by putting my course syllabus on Moodle and use it for registration.
I prepare a web page that includes all links I will use in the discussion
The participants at the scheduled time are called by Skype and we exchange pleasantries.

I direct them to the Home Page of the discussion which has annotated links to various resources.
I turn on my web based whiteboard and explain how it works.
I give them the password that lets them see my monitor.
What else do I need?

Why do I need a set platform that I may not own and may have to pay for?