If you get your application approved without documentation does not mean that they will not reject other person's application without documentation. They clearly say on their PDF while you file online is:
Next Steps:
Send supporting documentation to the address below, if required.
• For information on required supporting documentation for this application, see the BCIS Form Instructions links listed at the following Internet address:
http://www.uscis.gov/graphics/formsfee/forms/index.htm.
And if you look in the I-765 form instructions:
Employment-Based Adjustment Applicant--(c)(9).File your EAD application with a copy of the receipt noticeor other evidence that your Form I-485, application for permanent residence, is pending.
I guess in your case they did not look for the documents and this shows that how bad the USCIS is with the integrity of theri employees. But this does not mean that you do not need to send any documents.
I understand that from your experience you may think that it is not necessary, but if you read the instaructions, you have to file the documents, else you will be answering an RFE if the officer is wise enough to check for the documents. Sometimes RFE can be time consuming and should not be left on chances.