I'm no food technologist but squeeze an orange and put it in a glass, which is pure orange guice (100%?) and leave it on a table, and do the same with the 100% store bought one. The one from a bottle or cardboard box, not the "squeezed today" ones which are refrigerated. There will certainly be a difference, the freshly squeezed one will be stale, possibly ransid within a day. The bought one, not so sure... So there is obviously "something" else. Either preservative or some process done to the fruite.
Not to mention the taste.