I hung on to all of my garbage while walking the Tahoe Rim Trail in order to figure out just how much trash I generate over 7 days of backpacking. It was surprisingly little, even though I packaged two of my meals in Mylar bags, which are much heavier than our usual ziplocks. On our long thruhikes we generate even less trash. For these, we re-use the ziplocks we ship our dinners in for breakfast and lunch bags later. At home, we minimize consumption and recycle everything possible, but our weekly trash payload is still much higher.
Blog posts from my trip, including a gear list: https://thruhikers.co
Our book: https://geni.us/Thruhikers