It's not so much that they were replaced but that the logistics of delivering an entire house's BOM to a single location didn't make sense. What made it work at

It's not so much that they were replaced but that the logistics of delivering an entire house's BOM to a single location didn't make sense. What made it work at the time was the railroads. The lumber would be dropped off at a freight yard to be picked up by a local contractor. (Although the homeowner could have done it themselves if they wanted the actual work was typically hired out to tradesmen.) But as the country shifted to highways, houses were being built in places that weren't accessible by train.