Mercedes and Land Rover offer free drinks and snacks (cake, crisps, chocolate, pork pies, sausage rolls, popcorn) at their showrooms..
The coffee is freshly ground and excellent quality at Merc. They also have comfy sofas and sky TV so you can sit there for a few hours and enjoy.. Totally FREE!!
You can usually just go in and take a quick wonder around then take a seat and stock up on your favourites.. And 'return later' to properly check out the cars ..