I'm with you on this one. My general opinion is that (as long as we're talking enterprise disks) SATA drives are enough for most functions. Only databases and similar functions with high demand IOPS *need* SAS. Of course SAS and SSD drives will make overall performance way better, but SAS drives are expensive and SSD unreliable in the long run. Therefore, SATA drives win most the time.
I've been using enterprise SATA drives in most servers and computers of more or less importance for at least 10 years, and I've only had problems with a handful. Not enough to believe SATA drives have less life expectancy. Consumer drives on the other hand... that's another story.
And you can do a lot to up the performance of SATA drives. Faster disks and better disk controllers for one thing. What RAID level you go with is another. There's a huge difference in a parity RAID and a RAID 10.
The basis for the construction always has to be demand, that's my point of view. And since I'm working in the SMB sector, price is *always* the primary issue. Why waste money on overkill if it could be your own profit?