Dave, I said:
I can't see Marple welcoming them in the way that Costa has been welcomed
This is nothing to do with my preference but that of the amorphous "Marple" entity. When they were much younger, I took my own kids to McDonalds for what they considered treats (Happy Meals toys etc) and I have been known to wolf down a Meatball Sub on the odd occasion.
For whatever reason, and I'm happy to be proved wrong, my impression is that the nice interiors at Costa (armchairs, wooden tables etc) contribute towards the feeling that, as a chain, it is considered superior in some way to the bright tiled plastic interiors at, for example, McDonalds.
That's too many commas and sub-clauses, but I expect you get my drift.