It could be different in Australia, but in the US, you can get a DUI on a bike the same as in a car. There's no differentiation on the books. Be sure to check your local laws before drinking and cycling. :)
You can usually get a DUI on a bicycle, but they're much more self limiting - if you're too drunk to bike, you can't get on one and get it going. On the flip side, if you can get on and get moving, it's fairly easy to keep upright and in a somewhat straight line (plus, bicycles normally weave a little bit anyway).
The DUI-mobile of choice varies depending on the area. In a lot of other places, it's a 50cc scooter (usually doesn't require a license) - an adult on a gutless wonder scooter probably is there because of DUIs.
In any case, I'm fairly certain you can't be banned from bicycling - even if you lose your license, a license is not required to ride a bicycle, so it's a valid method of transportation if you've lost your license.
1. Kudos for being an activist. E-bikes are probably actually MORE efficient than a straight pedal bike if considering the financial/environmental cost of the extra food.
There's evidence of that, yes. If you're in a low carbon electricity area, absolutely. Food production in the US is absurd. And while you've got some energy invested in the bike/motor/battery, the amount of material involved is radically less than EVs. I've got a ~7lb motor (it is permanent magnet, so probably some rare earths), and a ~500WH LiFePO4 battery. So, 170 of my batteries makes up a Tesla battery pack (in terms of capacity). I have a 15-20 mile range on significant motor assist, and could trivially bump that up with a larger pack if I needed to (or if I were hauling more weight, like a cargo bike). The efficiency of a bicycle is insane, and ebikes keep that insane efficiency.
Though, as one of my pure-pedal-bike coworkers pointed out, the cost of extra food only matters if you're not trying to burn excess off. An awful lot of people could commute for many, many months on the excess stored fat without needing to consume any extra food.
Down the road, I may get involved in building my own variety of ebike (both commuter and cargo) - I've learned a lot about what works and what fails, and while mine would be expensive, they'd also be quite reliable, and I could undercut the full custom ebikes by a good margin (using off the shelf parts instead of custom designing a frame).
2. Probably the biggest issues with knee/hip pain are improper bike fit (I'd say 90% of cyclists I see have their seat WAY too low), and inadequate low gearing.
Likely, though it depends on the nature of the injury. I view any transition off a car as a huge win for everyone involved, so I'd rather see people on ebikes than in EVs. :) Most people think I'm nuts for biking in the rain, and I think they're nuts for sitting in traffic in the rain when there are perfectly clear bike lanes, so it works out.