Just like home

I understand the appeal of Starbucks.  They have free Wi-fi, clean toilets, and excellent coffee.  Even their bagels are passable.  But why is MacDonald's so popular?  This is not just in the US or the Czech Republic, but all over the world.  Czech food can be a bit heavy, but for grease and empty calories, there is nothing like a Big Mac.

Above: One Prague's many Czech Starbucks coffee shops.
Below: Czech and Chinese MacDonald's.