maybe quite a few have looked into it, but when they find the cost of replacement batteries they think somebody's having a laugh.Electric bike are also expensive. Most people don't ride bikes that cost £1k - they ride bikes that cost £150 from Halfords.
Oh, and to the cheating comment - I always reply "so did you cheat when you drove to work this morning? My bike is a form of transport, not a form of exercise - and a form of transport that costs me 6 pence each commute". They normally get it then.