This is wrong no matter what way you look at it. I think it is fairly common around the world though. I recall looking for a property when I was returning back to South Africa and the lady heard I was phoning from England she removed the sale price and added another R500 000 on the price which is about $30 000 extra. I didn't buy it even though I wanted it out of principle. I should have bought it though as it was a good deal still.
Yes it's true, it's everywhere like this but it's done and shown to everyone more indirectly ... But it's good to know, In all cases we should negotiate. :/
I recall a girl i knew that had this older Australian couple that she was trying to "help them get a good deal" on a locally owned Thai business. The "good deal" she was getting for these people that she was friends with to the point where she called them "mama and papa" and the relationship seemed genuine, was nearly 3x the sale price of the business.
I thought differently about this girl from that point forward. She ended up marrying a rich Australian that none of us had ever met. I wonder if she even cared about the guy. Whatever, crooks are everywhere!