Good post, nofossil, that we should not be guilted into living in any particular size of home.
Home size is both a private and a public issue. The real cost of a home is not just the cost of land + building. On the private side utilities, taxes, insurance, and maintenance can loom very large over time. Add to this opportunity cost for other things the money to buy and own a larger home could have been used for, such as earlier retirement, education, travel, etc.
On the public side, sprawl and infrastructure costs are huge: roads, utility services, schools, hospitals, police and fire protection. Some argue to keep taxes low - no way to do that with the cost of sprawl. USDA reports that on average public services cost $1.34 for each $1.00 of real estate taxes collected on developed properties. That extra has to be made up from other taxes and fees.
Then there is the intangible social cost: a big part of which is pollution and environmental degradation. Pollution from energy use for our cars getting to and from our homes, operating our homes, and making all the things we use and throw away in our larger homes. Environmental degradation from deforestation for housing; fertilizers, pesticides and herbicides spread on lawns and washing into streams and rivers; erosion of soils; etc.
The key to all living is sustainability for the present and future generations, something we as a nation are not doing too well at. The smaller home is just one handle that some use to get a grip on a much bigger issue.
For my wife and I, our 1500 sq ft (with 3 children now raised to adults) is plenty, and the money we have saved in reduced utilities, taxes, insurance, and maintenance over our 27 years together has allowed us a lifestyle of part-time work and now early retirement. I can't imagine a larger home that ever would have justified us working longer and harder to support.