Probably is just abandoned....it has a few disconnected cables but other than that it's fine, air in the tires and all...no lock in sight....I am gonna leave it be for now, it has been a few days only
My theory on this is its like computers, something goes wrong they take it to the shop and get a crazy repair quote and give up. I bought my long tail super cheap this way after theft damage.
You're in Lausanne right? Could just be someone from the countryside who doesn't lock their bike. But you could always lock the bike with a note saying 'if it's yours, let me know and i'll unlock it'
Stolen and stripped? All jokes aside i have seen them without batteries for 300$ on german classifieds. I know someone with one and they like it