OEM Genuine Honda motor oil is made by Idemitsu. It's the same motor oil, but it's cheaper when purchased with Idemitsu name on the bottle. Rockauto, NAPA and some other autostores sell Idemitsu oils. Oreilly does not.
OEM Genuine Toyota motor oil is made by Mobil (according to Lake Speed Jr). At least for Toyota oil sold in USA. It might differ elsewhere in the world. As far as I know, all Toyota oil is synthetic oil. It's Mobil 1 oil in a Toyota bottle. You can buy the same oil for less money by buying Mobil 1 from Walmart.
I'm not suggesting anyone needs to limit themselves to those car brand OEM motor oils, but if you want to stay with them, then I suggest buying them from lower cost sources as I described.