This is just like the iPhone (lack of) storage and the (lack of) SD cards. Apple is trying to maximize profits by using less RAM and by forcing people into buying more hardware in a few years. Apple does a lot of stuff very well but then they also pull this crap.

Acknowledging that 8GB only delivers mediocre performance at best would upset anyone who already bought a device with only 8GB. And as later upgrades are not supported by Apple it would abandon these users like buyers of a 1st gen Apple device...

My guess is they're going to sell like hotcakes to clueless parents whose kids insist their first laptop needs to be apple

Its all on-die not on the board, so Apple gets to charge you more.