Nice set of documentary photos, Marie. Up here they make birch syrup rather than maple but it's the same basic process.
There must be something more to the story of their situation. Unless they do business differently in your part of the country at least.
Pipeline companies don't typically own the property that the lines run through. They usually pay the landholders a lease for use of the property. The 200ft wide easement that you mention can typically continue to be used for agriculture etc. Just can't have occupied buildings on it. Doing the math on 128 acres and the size of the easement you indicated, only ten percent or so of the farm should be needed for the easement. So say if even half of the easement is actually cleared (in you photo nothing near 200ft is being cleared) then that's five percent of the trees potentially destroyed. Unless the maple farmer has a terrible lawyer he should be able to keep his business and have a nice retirement annuity from the lease and/or royalties. Maybe he just needs a new lawyer...