I used to work in a photo lab.
The copyright laws are very strict, and the businesses must err on the side of caution.
It can be very hard to tell the difference sometimes, as you just found out, but if they just once make a wrong judgment call, and the professional photographer decides to sue over it, they stand to lose everything.
Try to understand that although it is frustrating for you, they are not trying to be mean to you. This law is just as frustrating for them. They run a business and WANT to help you, and give you great customer service.
It can just be very hard to distinguish, if a photo is professional or not. As you said, equipment is very advanced these days, and people are getting very good at picture taking.
If you are unhappy with this, instead of blasting the poor manager who is just doing their job to the best of their ability, put your energy into changing the law. It has not kept up with our changing times, and needs to be updated.