Liberal guilt (or 'Why, oh why did I throw that plastic bag in the bin?')

Hi any and all of you who might have found your way here.

The move is still in progress, sort of. I've got most of the necessary stuff, but still need to get more and have been out walking up and down streets looking for jobs.

I've been thinking the last few weeks, because I've not got much else to do, about how far is reasonable to expect people to go in terms of recycling, reusing etc. In my current situation, I have no counter-top box for food waste because for whatever reason, my normally excellent local council hasn't sent me one yet. For all my food waste then, I've lined a plastic bag with newspaper and been putting peelings, and leftovers in there to eventually put in my building's communal food waste bin outside.

Now I know lots of people who wouldn't bother. They wouldn't want the possible smell, or the hassle of any drips of food-waste tea that escape the bag. But for me, it just seems like the obvious thing to do. My waste bag (which thankfully hadn't started smelling) was half full so I took it out to empty it. I was left with an empty, dirty carrier bag. Which after a moment's thought I threw into the large general rubbish dumpster. It's been playing on my mind whether I should have held onto it and rinsed it out to use it again. The more I've been thinking on it the more I feel like that's what I should have done. I think when I go home I'm going to grab it out of the dumpster (which was full so it's on the top - I'm not going dumpster diving for a carrier bag) and wash it out and save it to use again. I hate that I have any plastic bags in my house right now, but I've not got my hefty-reusable bags with me at the moment either.

Anyway, to actually make a clear and concise point here: was I wrong to throw the bag away? Is it reasonable to expect people to clean and reuse dirty (with food waste, not like dog mess or something) bags when the only effort is running water and hanging it over the bath to dry? How far does or should the normal social expectation go in that sort of situation?

My major thoughts on the topic are to do with the fact plastic bags are awful for the environment, use up oil (especially important in our time of nearing peak oil) and the fact that I threw away something that could have been useful to me at least several more times.

OK, I'm now wracked with guilt. Even if I had to dumpster dive I would get that bag back now.

Hopefully I'll be back again soon. For now, take care.