When these machines first came about in the UK the law was basically the “random number generator” had to be supplied remotely and by a 3rd party. The results were transmitted by satellite.
In 2005 the law changing meant the results could be produced on site, such speed was required for games that required faster processing so you could have slots.
The amendments in 2005 to the gaming act super-seeds the previous, so I can only presume to allow remote gaming in a LBO would require new legislation.
All pretty pointless since if you have a smart phone you can deposit in shop and do exactly the bets you are explaining.
Would expect the high street operators to push their on line platforms in shops.