One of the food podcasts I listen to was talking about olive oil today and how olive oil quality is affected by exposure to the air. One of the reasons for the regulated pour spout on many bottles. But they also said that the air issue was a reason to NOT buy the humongous bottles of olive oil that will be opened time and time again and be exposed to the air. Or have separate bottles - the large one for general cooking but a smaller high quality bottle for olive oil that is more directed “eaten” - like bread dipping olive oil, olive oil poured onto hot pasta, etc.
Thought that was interesting.