Those dishes look pretty worn... I'm assuming that they aren't used anymore. There was a time (2001-2005ish?) where if you wanted to get your HD locals (if they were 148) and some of the lesser SD locals like secondary PBS stations, as well as get SkyAngel (the independent religious service that left 61.5, went to IPTV-only, then went defunct) and some international you needed 61.5 (for SkyAngel) and 148 dishes as well as a Dish500 or if deeper international was also involved, a DishPro(IIRC?) that was larger and could pick up KU bands at 105 and 118(?) and the standard western 110/119 satellites -- so 3 dishes; 2 wing dishes and either a 500, or a much larger DishPro in the middle if deeper international was in there too (maybe a few off the wall public interest channels were on KU as well).
I actually remember seeing a few churches do exactly this... I'm sure a few of the satellite geeks around here did that as well. There also used to be a few of the public service channels on either 148 or 61.5 but not both, and IIRC they split some of the east and west HD as well across them too... So a setup like this was either for religion or international as well as HD/lesser locals at the same time (if those came off of 148 for you), wanting to get east & west of a few HDs or every small public interest channel -- and absolutely getting every channel you possibly could -- and then add in the larger DishPro for international or some really off-the-wall tiny public interest channels.
IIRC, Dish got sued for splitting out the lesser locals like this because I think the law stated that if they had to carry locals, the entire market needed to be on one dish only -- they had been splitting them with the big 5 or 6 locals on the main satellite, then the smaller independents and secondary PBS stations on 61.5 or 148. DirecTV also had a wing dish for a leased 72.5 slot they had for a few years -- but it was all or nothing -- you either bought locals and added the wing dish, or you didn't get locals.
So to answer your question... the neighbors were probably early adopters of HDTV between 2001 and 2005, wanted religion or some international that was up on 61.5, and wanted all their locals which were probably on 148 at the time... there is or was probably a Dish500 somewhere on the property. Aside from that, they may have been members of this or another forum and just wanted to get everything because they could lol
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