Thanks for the signal-boost! I love seeing more discussion around this sort of thing. A couple of thoughts:

What if you bought the bottled drinks you like in larger-capacity bottles, like only buying coke in the 2 litre bottles, and then filling glasses or travel bottles out of that?

Wrt shopping bags, I can't recommend the collapsable backpack/purse-sized shopping bags enough. I think there are some links to places that sell them in the comments to my original entry.