Ever seen the SciFi series Firefly? They speak a mix of Chinese(Cantonese?) and English, mixing the 2 all the time its actually quite funny, swapping mid sentence.
That's quite a weird way of doing things. I do love FireFly

As to the OP, we would lose a great part of our English culture if that happened...
For one, the Great British past time of failing to learn the language of the country we visit, and instead just raise your voice and speak in really slow, patronising English with some stereotypical foreign words chucked in
