For what it is worth, idealrecycling.net is painted on the demonlition machines -- Ideal Recycling, Inc. is a scrap metal recycling outfit about 30 miles from Old Town.
Not so very long ago, C&D (construction and demolition) debris was indiscriminately used as fill, or was dumped in a landfill along with other waste. Environmental regulation prohibited the first practice (demolition debris typically contains asbestos, lead, and other noxious materials such as drywall, that contaminates water with sulfate and releases large amounts of hydrogen sulfide into the air when decomposing), and increased landfill tipping fees eliminated the second (landfills for municipal waste must now be built to prevent contamination of groundwater and air -- they are no longer just holes in the ground). So it now pays for demolition companies to remove as much reusable material as is practical, leaving a minimum of waste that must be disposed of by landfilling in C&D landfills designed to minimize pollution -- though not necessarily as stringently built as landfills for municipal waste.
I'm not familiar in any detail with Maine's solid waste and C&D regulations, and I don't know what is required when demolishing a site like the Old Town factory. In New York, there would not likely be many bricks left lying around -- they are often ground up to become a component of "clean" fill -- though painted bricks, like painted wood, can be difficult to deal with -- lead paint means that painted wood should not be burned; painted bricks should not become clean fill. Maine may not have quite the same requirements on some materials. The buildings containing steel, however, are the first to be taken down -- though I understand from Benson that some time was devoted to clearing out asbestos from all the buildings.