My fav photo gear store is CP so I've to speak up for them here. Hell, I go to them even when I know for sure their prices are higher than others
The staff at CP are generally friendly and helpful. I've got to know a few of them personally over the years I've been patronising them.
Like many stores, the prices quoted by CP staff has something like a 'built-in buffer'. If a customer is a regular, he gets more freebies/discount. Period. So I guess the staff who quoted your bro $1 less simply gave him a better discount, that's all.
I usually get to pick up more freebies than most customers when I shop at CP. Plus I get to chat with my friends who work there, which are always very enjoyable. These make me go back time and again. And also prompt me to recommend my friends to shop there.
Good customer service is always a huge drawing point.
Ask me to shop at AP???? Over my dead body. Well, almost... ;p