As an international applicant, I must not only provide an official transcript, but translate it and, as Blanche Dubois, depend on the kindness of strangers in university bureaucracies to sign, seal, and return it to me, so I can ship both documents. For my grad school transcripts I had to come look for my course director in three different days. He just needed to say 'ok'.
The process is so tiresome that I actually gave up on applying to one school since for that I needed to go over the martyrdom all over again. If a transcript had been lost in mail, I would probably say 'the hell with it'. Why they just don't accept scanned transcripts? I would provide official copies if admitted, believe me. Some say it is a way to increase the opportunity cost of applying, but I find this view nonsensical. GRE's, TOEFL's, begging for LOR's, SoP, and more is a price no one would pay unless he/she is willing to get their PhDs.