Because it tastes good that way.
Which surely must be the retort to the original posting in this thread!
Overall though, things are different between the US and the UK, not just food, but driving, shops, schools, clothes, customs,
etc etc etc. If you are planning to stay then it
must be best to come to terms with the differences rather than for ever wish things were different.
I moved to the US last year and some things are weird to me too, I could wish they were different, but things won't change just for me. So, as this is now my home I take things as they come, differently!