That’s not how most apps work. They tend to allocate memory for specific purposes and free it when done. Only more heavy apps will retain large buffer pools, like databases but they are usually tunable. And apps themselves don’t page to disk, usually. The OS does that. Before we had MMUs apps like photoshop used to manage the page file manually. But again an app doing that is doing that for a specific purpose, not just to be greedy.

Is there some specific software you are referring to?