That is the couple's dynamic, they love each other, Wayne isn't bothered - and I think it comes from Tom's worry, if Wayne does not lose weight he will die early.
And, Wayne kind of condescends at Tom too, more about his work and intelligence.
Different couples have different ways of being.....I never go there, due to my own parents utterly weird dysfunctional interactions.
We grew up thinking they would/should divorce, only to discover once they got rid of 8 kids, they were like young lovers again!
And, when Mum died, I took care of dad for a few years, and he tried to get that weird dynamic going with me - had to give him stern warnings several times not doing that Dad.
My bestie gay male friend shares my birthday and I love him dearly, he is however the biggest bitch I ever met mouth wise, I find it funny.
I love how he cuts through utter crap - like my drunk sister got a great serve when we were in WA last year, was friggin aweseome.