I wouldn’t buy a machine with 8gb and the MBAs are just extracting value from their customers.
However as an engineer interested in efficient software, I support what Apple is doing here. If there is a significant number more of machines with just 8gb, it forces the software developers to think and consider these folks to keep their software less bloated. I’m not talking about professional apps like photoshop, but regular things like email clients and browsers. I feel browsers and bloated websites can optimize their memory consumption here.