Huge tracts of land that have been derelict since the blitz will be re-generated for jobs, homes etc. IMO London and it's communities have still not recovered from the devastation that occurred over E London - attention moved away from the E End after the war, the docks were moved to Tilbury, communities were dispersed and under-valued etc etc, there has never been investment in TRansport to the east of central London.
But the use of sporting facilities will spread for miles. Contractors and manufacturers all over the country will benefit - factories in Stoke or Teeside will have just as much chance of getting huge contracts for t shirts or paint or stop watches or sun visors as anyone else. THINK of the huge manufacturing and retail opportunities. The textile industries around the countruy must be going bananas with delight! And all these things will be up for sale to tourists etc.
Think of the ice-cream manufacturers and soft drinks, and all that beer brewing in the midlands....it's a country-wide bonanza, if we market it right.
And international visitors will be very tempted to travle to attractions in other parts of the country...
And our athletes will come from all over the country....
There is no way this is a London-only opportunity.