I don’t agree with the idea that oil and filters are cheap.
Take the Barras: 5W-40 FS costs me about $8/litre in bulk, and genuine filters just over $10 apiece. So, about $65 in my costs - of course, free of labour charges.
That’s a good half of the weekly shopping cost. If you pay retail on a name brand oil, you’re going to be well over my spend. I’m not going to be the only one here who notices a sixty-five dollar hole in their wallet. And realistically, from the neglect I’ve seen on various motors, stretching an NA Barra to the far end of “ideal” isn’t going to drop the sky on your head.