The feature that auto-picks up money and ammo is neat, but seems very inconsistent; sometimes I auto-pick up money and ammo that I need, sometimes I have to manually pick items up. I'm talking about the feature that collects without a button press, not the long-press action that picks up all "minor loot" in the area.
What's the trick? Are enemy-drops auto-collected and container loot not picked up? I think I've been observing that but I'm not sure.
Best Answer
The auto pickup system specifically only picks up ammunition and money.
In co-operative mode you share ammunition so you never have to feel like you are stealing ammo from someone.
A possible explanation for the issues you're experiencing could relate to similar behaviour from the original Borderlands in that latency could allow you to pass an item without picking it up.
You're not the only one who has experienced this behaviour, several gamers are reporting the symptoms of ammunition and gold not being automatically picked up.