to me being green means recognizing old wasteful habits and replacing them with at least the most basic green ones. for starters,reusable bags.but don't be shy or bothered when the store clerk or the other people in line roll their eyes,and sometimes they will. just say,"i'd like to use this please". and use them in every store you enter,not just for groceries. i want to shrink my carbon footprint to a pinpoint.
Plastic, because we always need bags for dog doo.
Paper. In fact during gardening season we ask for paper bags. We use them as 'planters paper' in the tomato patch - as weed blocking. Very effective.