If you are looking at an item record or saved search and do not see a preferred location, do not assume the information is missing. When items are set up in multiple subsidiaries, the preferred location information moves to the Development subtab. It is housed there because each subsidiary has its own set of preferred locations.
FYI- for a list of all active Multi-Subsidiary items, you can use this saved search: https://5050497.app.netsuite.com/app/common/search/searchresults.nl?searchid=10153&whence=