Well I use "owt" all the time, and say it too. I take it to mean "anything", same as "nowt" means nothing. i.e. "I haven't got owt" = "I haven't got anything
", and "I have nowt" = "I have nothing". Might seem pointless but it feels natural.
So, in my interpretation and maybe theirs they may not mean "owt" as in "out". Depends on the context though ^__^. If they said "I've gone owt" then they just must be stupid and irritating.
Though, along with your point, people who put "Kool" instead of "cool" are just..![]()