Bicycling to the Grocery Store, Take II

Today I made my second fossil fuel-free grocery-getting trip using my bicycle. I'd like to give five reasons why doing my shopping by bicycle is working and five reasons why it isn't working.

How it works:

1. It's great for the environment. Bicycling is the most efficient mode of transportation humans have ever invented.
   
2. It contributes to better physical health and makes me feel good.
3. Round trip, it's only 2.2 miles and mostly flat.
4. Hannaford, the supermarket I frequent, is located on Main Street in Waltham, so I can stop at CVS and other local businesses in the same trip.
5. The busiest road I take (South St) is wide enough and the traffic goes slowly enough that I feel fairly comfortable bicycling.
   

How it doesn't work:

1. I can only carry one (large reusable) bag of groceries on my rear rack. Even with just the one bag, the situation is rather precarious because it fits into a cardboard box I rigged onto the rack.
   
2. My rear rack is attached only to my seat post and not the rear hub. Under the weight of all the groceries, the bottom of the rack rubs the rear tire on even the smallest bumps in the road.
3. South St, while having relatively slow-going traffic, does not have bicycle lanes or even a marked shoulder. Drivers feel like they own the entire road.
   
4. The weather is great now (70 degrees and sunny), but in a month or two the conditions won't be so great for bicycling.
5. Most times when it occurs to me that I need to shop for groceries I'm at least a little hungry. It's not so great bicycling on an empty stomach.