RE Headaches #1: Lenders let "As-Is" Appraisals affect the loan??

[Jimmy O'Connor]

I was recently working with my investor to lock down a property in West Philly and his lender changed the rates since the "As-Is" appraisal came in 15k lower than purchase price of the property (the appraiser ignored the condition of the property and comparing it to properties that were damn near shells, but I digress.) As a result my buyer had to bring an additional 33k to the table when he was originally expecting to bring 13k, which caused a little bit of chaos since this was all found out literally the day before closing. 

To my hard money lenders or investors that understand the process better than I do, why do lenders account for the "as-is appraisal" when, in all reality, the ARV is what is going to be influencing the borrower's ability to satisfy the loan?