Enterprise Inns own the Somerset house premises, and want a regular rent payment in the current climate of Pubs struggling. So they are happy to invite Tesco into their business plan because they will receive rent regularly.
However, the Pub has been (apparently) profitable & succesful with the current tennants so, all is well for now.
I must admit, I've seen the car park completely full on occasions - you don't see that very often nowadays.
Furthermore, its an historic building, built before most of Calow as you see it today.
Why desecrate it like the debacle which was once the White Horse in Whittington?