The pull toward other sports is too big in England. Why on earth would you want to make chump change getting beat in the face? You have access to THE best Football and Tennis camps in the world. You also have Golf and Cricket. All of which have more (or as much) potential for money. Most of which you do not need a part-time job on the side if you're in the top 10% in the world. All of which involve much less brain damage and pain/suffering.
I mean, hell, in League 2 in England (that's not even A-Ball equivalent for us Yanks), you make an average of $1,500 per WEEK. Imagine!
You may doddle around $50k a year to be not anywhere close to the top flight. All that without getting punched in the face or your shoulder ripped out of its socket. Why on EARTH would you want to fight if you're athletically skilled and in the UK?