A lot of universities initially just mail you scanned PDFs of their letters of acceptance or they mail you a PDF with a scanned signature on it rather than an obviously original signature made with pen. It takes a bit longer for the original, signed letters of acceptance to reach international students, so often people just submit the scanned PDFs or PDFs with scanned signatures to begin the Study Permit visa application.
Simon Fraser University was initially doing the same thing with me, but I know how cruel these embassies can be so I forced them to send the original, signed letters to a friend of mine in Canada who sent them to me in Islamabad via FedEx.
Really, the whole system is messed up on a number of levels.