VFS Global and Supporting Documents Submission [closed]

After having my supporting documents for a UK Visit Visa scanned and uploaded at a VFS Global centre, it was my understanding based upon what I had read on the visa4uk.fco.gov.uk website that the actual hard copies of the documents were then no longer required to be submitted and that they would be handed back to the applicant immediately after being scanned. However, this was not the case with my documents. Upon completion of the scanning, the VFS employee did not hand my documents back to me. It was only when I requested the return of the documents that I was told that unless I really needed them that sending the actual hard copies as well would support my application.

My questions are as follows:

Firstly, considering that VFS Global have - one would assume - correctly and proficiently scanned and uploaded the supporting documents themselves, as opposed to the DIY applicant who may mess up, why would VFS also want to keep and submit the hard copies as well? And secondly, can anyone confirm whether the hard copies are in fact sent to the embassy or whether they are kept at the VFS centre for reference and referral if and when required by the relevant embassy?

Thanks