Many campgrounds have two sewer inputs and they could certainly be used if needed. I think they are mostly to accommodate the different evolving types of campers.
I believe with many floor plans make it difficult or expensive to pipe the distant drains internally so the easy way out is to have them in different locations on the floor plan. Not to convenient for the user. I see a lot of them lately with a external Y connecting them together.
2011 351RLTS Eagle, Mor/Ryde suspension & pin box
06 F350 Lariat PSD, SRW, LB, CC, EGR delete kit, 16K DrawTite hitch, Timbrens, TST TPMS
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