By the late 1960s, most American malls were being developed without supermarkets. The primary reason for this shift was that the mall, in general, was becoming more upscale. Middle market stores, such as 5 & 10s and supermarkets, were being eschewed in favor of additional shoe and apparel stores and so-called "luxury retailers."
The placement of a supermarket as part of a mall had also come into question. Whether or not a shopper would do mall shopping and food purchases in the same trip was pondered. Supermarkets were, by nature, a low profit-margin type of operation. Grocery companies could no longer afford rapidly-escalating common area charges that were levied on all mall tenants. Moreover, parking and easy road access to and from mall-based markets had become an issue.
By the mid-1970s, few newly-built shopping malls in the United States included supermarkets. Most of those in existing locations would be shuttered and repurposed by the mid-1980s. Many had their spaces divided into smaller inline stores or food courts. In other cases, a supermarket structure would be demolished and replaced by a large department store or new mall wing.
In other parts of the world, the supermarket / mall combination continued to be seen. Australian malls almost always included a grocery store or stores. Some new operations in Canada might have an attached supermarket. What few malls that were be built in the United Kingdom might include a supermarket, as well.