Actually they destroy then directly and indirectly. The goverment closed all the casinos and nationalized all hotels and small business main users of neon lights. Once every little business was taken over by the government, no one really cared anymore since they belonged to no one so they slowy broke and no one cared to fix them. This a reallity for Cubans living in Cuba right now(I'm a Cuban myself but I do not live in Cuba anymore) with many other things like buildings, roads, artworks, no just neon lights. And of courses suporters of the regime will blame the US for it like with everything else.