It could be that current homeowners in Sidney grossly overpaid for their homes to begin with and are now about to experience to bursting of the housing bubble that the rest of the country experienced eight(ish) years ago.
Due to supply and demand housing prices were through the roof in Sidney. Sellers could (and did) demand a premium for their homes. Just research home sale prices- each consecutive sale for an individual house each owner would ask an increasingly outrageous higher price.
Compared to homes in surrounding communities the Sidney market was artificially inflated, but people moving to Sidney had no choice but to be a part of that cycle due to the remote location Cabela's chose to call home.