if hey advertise $15 then yes you should expect to only pay $15.
If you see a brand new car advertised for $5000 to you just blindly buy it?
If you see a brand new pair of jeans at a discount store for $1.99 to you just blindly buy it?
If you see a home valued at $400k priced at $200k do you just blindly buy it?
....If you see a sketchy looking locksmith link in google ads that advertises generic "work" for $15 do you just blindly buy it?
It's unfortunate that we live in a society that isn't expected to even remotely protect itself. I feel for Nick, and I do think he was scammed, but if you think you're getting any sort of decent service in the middle of the night for $15 then you are going to get scammed. There must be some catch, and it looks like Nick unfortunately found it.
I'm not saying it's "right", but you can't expect to just blindly call some random ad you found on the internet and get quality service.