This ^^^^^^^^^^
It all depends on the oil, filter, and what the establishment pays. If you're a commercial oil change outfit like Jiffy Lube, you purchase your oil filters by the pallet load. And your oil by the tanker.
It would be difficult, if not outright impossible to undercut what they're paying for what they're pouring into your crankcase, and screwing on your engine block.
A local mechanic who is a one man band, or just employs a couple of guys, is going to have to charge more, because he is going to pay more.
That doesn't mean he's doing it for nothing. His profit margin will be somewhat less. Also, you're more likely to receive a lower grade oil from Jiffy Lube, unless you ask, (or they are successful in selling you an upgrade).