we have the same oil over here. It became unfashionable when lie nielsen videos came out touting camelia oil.
naptha is also sold as "lighter fluid" over here, too - you're right. It's just a cleaner version of gasoline as far as I know. Paraffin is generally the cheapest wax for candle wax, and it's also used (or used to be) as a seal when canning because it has a low melting point......and is cheap.
mineral spirits over here is a refined form of kerosene. I once tried to cross reference a post in a UK forum about terminology, but by the end of it, some of the folks thought naptha was mineral oil and that lighter fluid and naptha were drastically different. I'd imagine this kind of thing is a problem for engineers who come from England to here and thought that we all speak the same language.
Mineral spirits is also the least expensive form of "brush cleaner" for oil based paints and varnishes sold over here. THe most refined type is sold as "odorless", but chasing this stuff, as you say, isn't really necessary. there are many non-drying oils available - the cheapest may be medium mineral oil sold as "scent free baby oil".
A 50/50 mix of mineral oil and beeswax makes for a nice non-drying wax for anyone who wants to put a very thin coat on something but doesn't like the solvent smell of the drying wax types.