It's not just branding, IMO. I already looked into this. The average butcher shop has 3x as much revenue as a restaurant (at least in Holland). And the cost of setting it up is far less than building a restaurant. They have to give up some margin to Tesco but that should still leave them with 10%, maybe 15% gross margin.
So if they have only 5 of these butcher shops operating then that's the equivalent of 15 medium sized restaurants. Not exactly peanuts.