Trek Belleville

I know this isn't designed for hard riding, but surely integrating the handle bars and stem with butted joins is incredibly weak, no?...I mean for a bike that probably weighs 3 tonnes.

Weaker than seperate components yes, just look at what happened to Khe's attempt at a 1 piece bar/stem combo, I think it was laughed off the market just as quickly as it was broken and shown up for the stupid idea that it was, purely an aesthetics decision, as opposed to one based on function.

Mr muggles was very disappointed once his nice bmx bike got taken away from him: