My form.data property all looks like I expect it with one exception. It has an item called lstContractorAssign. I do indeed have this component on my app but it is not in the form.
If I change the Form data key on this component the form's data property changes as if it were in the form.
Interesting...I see this has come up for 1 other user before, but we weren't able to reproduce the issue (on our end or their end). Do you know of any repro steps, by any chance? 
I have not tried to repo it so I am no help there.
However, I did have a few duplicate Form data key values as the result of copy/pasting some components and this created odd and confusing result in form.data until I fixed them. I also had a combination of components with default values in Form data key.
I believe this might have also started out as a container before I created a form and moved the components.
So basically I did my best to confuse the bleep out of the thing so maybe left some lingering damage in the app definition as a result?
Thank you for the note on copy/paste and container -> form. Will also try my best to confuse the bleep out of my app to hopefully reproduce this!