how do you move your groceries? The problem for me has never been getting to the store; it's been taking my stuff back home from the store.

Uh, we have a baby, so: http://beststrollerreview.com/wp-content/uploads/2011/10/UPP....

In Chicago my wife would bring a rolling suitcase. You can also use something like this: http://www.walmart.com/ip/Whitmor-Rolling-Utility-Cart-Blue/....

We have these black rolling carts where I work for carrying around litigation documents. I'd imagine something like that would work too, and look less bag lady-ish.

When population density goes up, you are more likely to live close enough to your grocery store to make multiple smaller visits and make quick visits for one-off items you might need. I rarely ever buy more at the grocery store than I can carry on my own and I find the smaller more frequent trips much more convenient than having to plan around one large trip to a more distant location.

Lots of people here in seattle will take a bus to the store and a taxi home.