A person riding a bike has to consume extra food to burn energy in their muscles to propel them. The energy has to come from somewhere. There are CO2 emissions associated with producing food.
Why should regular bikes use more energy, given they're only manufactured once (as are bikes), have no degenerating batteries and don't need electricity are less efficient than ebikes?
It's strange that they didn't include the food offset by the ebike though. This link tries to give a comparison between the two accounting for a typical European diet (which is also far more sustainable than the typical American diet).
Yeah, doesn't quite make sense unless it's implying that it's within the average lifespan of the vehicle. Maybe then you can get further on an eBike than you can on an equivalent regular bike before it falls apart?