In the dumps, an idiom for the blues, extends to collective sense of despondency, unhappiness tending towards despair. It’s not despair, only a group sense of loss dictated by mood and circumstance. Dumps is a plural noun for rundown dwellings, neglected premises. For those on the street, this may be a packing case under the Brooklyn Bridge. In June it is shade, in January you could die in the snow. The verb explains this state of affairs. People dump on other people. People dump other people. They send them to a dump site, believing they’ve solved things. People dump responsibility.