This has always confused me - oil changes

[Jeffblue]

ok so this has always confused me. I do my own oil changes, but this is more of a general curiosity that always comes to mind when a friend or relative tells me they had their oil changed at a shop.

Many places will do a conventional oil change for anywhere from 25-30 dollars. so that includes labor and oil and a filter (Supposedly... if they actually do what they say). Then you hear about people paying 90+ for a synthetic oil change. so if you take 5qts of mobil1 which is 37, but lets call it an even 40 dollars for 5qts then a typical filter is 6-10 dollars, we're at about 50 dollars in parts for the oil change. then they proceed to charge you 40 dollars labor to do the same exact labor involved in a conventional oil change.

So why is the labor 40 dollars for a synthetic change, when the same place would charge you 25-30 for oil, filter, and labor for a conventional change.... am i missing something?