Where i commute there are a lot of electric bikes but they are easily recognizable. Besides the fact that you can see the electric motor in the front or rearwheel you can also see the rider being very relaxed and not sweating whil still maintaining a pretty descent speed. I guess the electric bike is the result of our instant gratification culture. Someone want to ride their bike, they want to ride it fast but they are in terrible shape and are not willing to spend time training. They want it NOW. So they buy an electric bike. But hey, every motorist who switches to a bike in whatever form is one less car on the road.

I also think electric bikes are an extra challenge, especially uphill they are usually still slower due to lack of training and eventually you still have to pedal to get moving. The electric motor still only supports the rider.