Many of them were eventually absorbed by the companies which had been their principal suppliers. From the mid-80s to the mid-90s, nearly every major urban area in the United States had at least one (and sometimes two or three) local direct distribution warehouses that functioned not only as distribution points for pre-ordered weekly shipments, but also as what could be described as "supermarkets for retailers", where store owners could shop for reorders and examine and purchase product that they might not have ordered in advance. 1990s As newsstand sales continued to decline, the Direct Market became the primary market of the two major comics publishers (DC Comics and Marvel Comics). In the late 1980s and early 1990s, as the popularity of comics collecting grew, many new comics shops opened, and existing retailers (such as sports card shops) joined the Direct Market, carrying comics as a side business. By this time, Diamond and Capital City each had approximately twenty warehouses from coast to coast, and both were functioning as fully national distributors. Several of their larger remaining competitors, notably Glenwood, Longhorn, and Bud Plant, had either sold out or gone out of business. Such rapid growth (due partially to speculation) was unsustainable, however. The market contracted in the mid-1990s, leading to the closure of many Direct Market shops. Diamond and Capital City began closing local warehouses, moving from a decentralized model in which many local warehouses provided full service to a given area to a centralized one with a few shipping hubs and no local walk-in service at all. In 1994, Capital City created controversy by announcing penalties for publishers who didn't deliver their products within promised deadlines; this move followed an industry-wide push for 30-day returnability, a practice formerly in use when comics were primarily distributed in newsstands. In early 1995, Marvel Comics purchased Heroes World, by that time the third largest distributor behind Diamond and Capital City, with the intention of self-distributing their products; Heroes World also stopped carrying other publishers' books. Other distributors sought exclusive deals with other major publishers to compensate for the substantial loss of Marvel's business. DC Comics, Image Comics, Dark Horse Comics, and several smaller publishers made exclusive deals with Diamond Comic Distributors. Most other distributors, including Capital City Distribution, Diamond's main competitor at the time, either went out of business or were acquired by Diamond. Others established niches — such as re-orders —