Dialect maps in everyday (German) life

In Berlin right now, en route to Leipzig for a conference and I did what you do in Berlin early on Sunday morning when your hotel room isn't ready yet ... headed to a bakery for a cup of coffee and a pastry.

I'm sitting and sipping and look up and lo and be-freakin-hold, what do I see on the wall, but a giant dialect map of words for 'roll' in German. It looks pretty homemade, but not quite and the place (Kamps) is a chain, so I'm wondering if this is a staple in their franchises?