Reinheitsgebot... why?!

Reinheitsgebot - holding back the development of more-interesting German beers for 500 years.  This Bavarian beer law, enacted on April 23rd, 1516 restricted beer ingredients to Water, Barley and Hops.  With growing scientific knowledge, Yeast was also added to the mix.  The Germans seem very proud of it, but I think it seems like a terrible waste of a brewing industry.  Think of the modern beers that would need special permission to be brewed n Germany - fruit beers of all sorts (addition of pumpkin, cherry, rhubarb, rasberry, etc.),  veggie beers (jalepeno peppers, sweet potatoes), milk stouts (addition of lactose, a milk sugar), wit beers (usually containing at least orange peel and coriander), spiced winter ales (clove, cinnamon, etc.) herb ales (made with lavender, heather, chamomille, oregano, gruit,, etc.) coffee and chocolate beers, beers with added rye, oatmeal or  wheat (though some exceptions for this do exist under reinheitsgebot), and honey beers, or any crossovers between beer, mead and wine.  Now, to be fair, it seems like the current german beer laws are more relaxed, though still somewhat restrictive, using taxation rather than outright prohibition to control beer content.  And the EU has weakened a lot of the restrictions, too. But this archaic law is still used as a marketting tool in Germany (and the US)!  Why would anyone think this was something to be proud of?  It’s like saying “In order to preserve the purity of our nation’s paintings, they may henceforth only be painted using the colors red, blue, black and white.”  You might get some interesting workarounds, but wouldn’t you rather have access to the full range of colors?