Truthfully, because a bios flash--though much safer than it once was--still carries a small risk.
Back when flashable bios was still a new idea, a bad flash (or an improper flash) could kill a system and necessitate a replacement of the bios chip. I cannot remember the last time I hosed a system with a flash, but it DOES happen--especially if people don't follow directions (in the case of a notebook, the number one issue is people flashing while on battary)
The rule is -- flash if you are experiencing a problem.. Many people flash just because it's new.
I never even asked Sager to send me the BIOS, but I had reported the problem some time ago and when the BIOS came out, they sent it to me out of the blue.
wahyagar, check your email