Alta Bates Medical Center $850 for a 10 minute Ultrasound is Too Much Oakland California

Hi folks, thanks for helping me out with your responses in advance.
Here's the story:
My wife got pregnant, and we were pressured to get an ultrasound - unfortunately before her insurance policy's "maternity" benefits were due to kick in. So we went to alta bates, and had a 10 minute procedure, got a picture taken, heard the heartbeat, etc.
Then a bill for $200 came. I checked it out on the web, and this is supposed to be the national average for ultrasounds, so I paid it and figured that was it. Turns out that was for the "technician." Whoah - $200 for rubbing some jelly on a belly, pressing some buttons and changing a paper sheet? That's $1200/hr - anybody here make that much? But it gets better.
Then we got the other bill for the visit: $1050 - and our insurance won't pay a cent.
Are you kidding me? For a 10 minute souped-up Polaroid? So we've been back and forth with Alta Bates, and explained a million times that our insurance wasn't going to cover it, that it is a significant percentage of our monthly income, so as "charity care" they lower it to $650, which brings the total cost (including the person) to $850.

Does anyone think this is at all reasonable? If so, could you please help me understand why it would possibly cost the hospital that much for our 10 minute visit? I'm a reasonable person, and if I can see that this is in fact a fair price (I understand they have to pay their staff, pay for the paper sheet, pay the rent, etc) I'll feel a lot better about paying it.

On the other hand, a new friend who works at Kaiser just told me that the people at Sutter, which runs Alta Bates, are crooks. If you agree with this, and think the "discounted" $850 is unreasonable for a 10 minute ultrasound, please let me know here so I can show them I'm not crazy in thinking this.

thanks so much for your opinions!

Dan
Berkeley, California
U.S.A.