If you are running under Windows:
Are you sure that the space usage isn't due to a dynamic-sized paging file? Look at the size of C:\pagefile.sys. If that is what is increasing dramatically, it is likely that you are using the default option for a dynamic paging file which may default to a much smaller size when in fact, for usage with programs such as 64-bit InDesign does require a larger paging file due to the larger address space it is using. I don't think you will find that InDesign is creating a > 7 GB set of temp files.
I'm on a mac. I don't know what is happening, thats why I'm posting here I do know that I was getting a "Hard Drive Low on Space" message which pretty much shut down my entire system before clearing out some additional storage space inorder to run the application.
Here is the difference. These were taken about 20 seconds apart from each other.