I think that's an LA vs. older cities thing. There are parts of LA where you can live that way, but not many. You can live that way in bits of Berkeley and certainly in many parts of SF. I'm assuming you can live even more that way in older cities back East. Of course, the flipside of that is that many places allow such urban decay that the older parts of their cities that are structured to be real neighborhoods are not places people want to live any longer due to the crime rate. The US needs urban renewal. Not in the "bulldoze them down" sense that existed in the '50s and onward, but in a way that goes to these older parts and cleans up the neighborhoods, fixes buildings, infrastructure and parks, gets serious community policing going, first time homebuyer programs, and incentives for small businesses that want to develop the storefronts (and help for them...they can't put in the kind of anti-theft resources a place like Walmart can, but Walmart is not what you want in these renascent areas).
I live in an area that used to be a small commercial corridor. It was entirely residential up until probably the early 20th century and then some housing was subdivided and a commercial block was carved out. (Apartment units above storefronts. The store owners presumably lived in the apartments.) If there were enough city, state, county and federal help, my 'hood, which has become plagued by crack dealers and a moderate amount of gunplay could be a thriving community again. Right now there are liquor stores, a 99 cent store, a cheap random tchotchke store and a barber shop. If we had a comprehensive grocery with a good produce section, a hardware store, a cafe, a restaurant and other anchor businesses, people wouldn't have to go downtown or to Emeryville for those things. Local young folks could get decent jobs instead of hanging around on the street and getting into trouble. But I have to say that if I were a small business entrepreneur, I'd be afraid to locate there. Not without a lot of city support and the support of positive African-American groups.
Still, I'm convinced that this kind of redevelopment is what will help a great deal. I'd rather see less flight to sprawl suburbs than making our cities more liveable again.