Hi James - Some use cases that we have are programs that are Profile specific. For example, WebEx Productivity Tools. If installed as System, they appear in Control Panel > Programs, but no where else. The user would have to located the EXE in the file system and open it for it to work.
Running as user works great if UAC is disabled, but UAC isn’t disabled on all of our endpoints, so it would be hit or miss.
OneDrive would be another example of a Profile specific installer.