the other is no different than stopping Tesco building a store because there is a perfectly good sainsburys down the road.
Your little world is a little naive, you can't build a Tesco down the road from a Sainsburys willy nilly.
You have to get planning permission. Which will look at several issues with relation to neighbours to the site, traffic issues demand for another shop issues, environmental issues etc.
What planet do you live on!!!. Oh right the John Lewis store - like its still not built!!!!!!