In a perfect world, yes. We would use less electricity if we realize we could. Unfortunately it doesn't work like that in the real world. In reality it has to make economic sense, as capitalism is "the way of life" in the western world (and many other places), otherwise it won't be thought of. We're slowly changing this.
Bitcoin is capitalism modernized, fully on the internet and on our computers. Since computers and the internet tends to multiply everything, we now have capitalism as a protocol, intensified like never before. Since being environment friendly is not a benefit for the participant in the network, it won't be a consideration.
A big fault in the protocol, and hard to see how it can be solved in Proof of Work. Luckily there are some people working on alternatives but we have yet to see if they actually work in practice on the same scale as Bitcoin.
