You're all a soft bunch really aren't you? Clearly no one here grew up in a country town in outback Australia. Just to derail the OP on my flight last Friday it was an Indian chap who did the exact same thing. If it is such an issue the crew should say something?

Personally I think wearing running shoes aka trainers with jeans and a tucked in shirt should be a punishable offence but you don't see me whinging about that after flying a US carrier or flying Qantas J class to/ from the US.

I look forward to flying BA F seat 1K in a few weeks in my trackies and t'shirt. I think I will even go to the bathroom in just my socks a few times. On arrival in Belgium I look forward to making everyone speak English, eating frittes and drinking local beers while standing on the side of the road and watching some bike racing! I will do so with a smile knowing how much it will annoy some here.