There's no way they changed that oil, I don't care how many miles were on that engine or how many were on your previous oil change, or if you drove 10 miles after that oil change. Your oil should not look like that after an oil change. Especially on a car with 40k miles, using synthetic. Nope.
I'll tell you what though, someone mentioned Walmart and extracting the oil through the dipstick...I would never take it to any place that extracts oil. Not because extracting oil is bad, but because the person doing the extracting is more likely to either not do it, or not extract all of it. It's too easy to skimp. Draining oil from a drain plug requires you to NOT skimp, simply because you'll get soaked with hot oil if you try. You have to drain all of it. When you extract, it is time consuming and no one would see that you have only drained two of the five quarts. There's no way to tell. Honest mistake...oh, I thought I got it all out. My bad. Woops. That's IF YOU GET CAUGHT. And you probably won't. And...oh I thought I put five quarts back in...yeah, I did. No record I didn't. Now all you're left with is a dirty paper towel when you get home for "proof".