No you philosophical bastard
Lion and Bianconeri gave a good explanation to me about it.Bale doesnt kill anyone.He was just someone with a very active imagination.He imagines all the murders.
No, you silly man.

He doesn't imagine anything, well perhaps some parts. Like for example when the ATM tells him to feed him the cat, that's probably imagination.
Even at the end, if my memory serves, when Bale meets the other brokers, one of them says Allen can't be dead because he just had breakfast with him this morning. And they all start laughing with Bale. See, they're all self-absorbed, most of them didn't even know who Allen was, thus no one noticed he's actually missing.