Over the years, Disneyland has offered a few different membership clubs and perk programs for frequent visitors. The first of these programs, Magic Kingdom Club, actually started all the way back in 1957, just two years after the park opened.
 Source: iCollector
The Magic Kingdom Club offered memberships to employees of local companies and local military members. Members received discounted tickets to the park, and in return, the local companies distributed promotional materials for Disneyland to local customers. The small but mighty program grew into a massive success, drawing memberships from all over Southern California and building a loyal fanbase. When Walt Disney World opened in 1971, the club went national.
Over the years, the club expanded to include vacation packages, airline and hotel discounts, and even a senior program. According to Yesterland, the club peaked at more than 30,000 participating companies and 6 million members!
 Source: All Ears
In its later years, the club spawned annual passes, group packages, and vacation packages. Eventually, Disney changed to a fee-based structure, renaming it the Disney Club in 2000. This was the beginning of the end for the club, which officially ended in the mid-2000s. Though there is no equivalent of the Magic Kingdom Club today, a few pieces of the original concept remain: Disney Vacation Club, annual passes, and Southern California resident deals.