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What you describe is the process of change from the apparent perspective of someone who does not like that change. Yes, eventually all that will be left is rubble, that is true whether something is behind glass for a while or not. Do you know the parable of the Buddhas teacup? It is all already broken and turned to dust, we simply haven't caught up with it yet from where we are.
Your examples are not too different from the idea of patina on leather, or craquelure on a violin.
How are the examples you describe not collaborations? Are you able to add detail to your argument in that sense?
I agree that we shouldn't just keep history behind glass. But that doesn't mean I support what amounts to arbitrarily damaging it for any old reason. 
The destruction of the Berlin wall is an intricate part of its history. The wall represented the split between east and west Germany, and the brutal repression of the communist regime. Tearing it down was the history. The same can't be said for people taking home souvenir chunks of historical artifacts. The relevant history of these things is often thousands of years old. When you visit the pyramids, what part of their history is more relevant: their construction and history concerning the society that built them, or Jim Nobody breaking some off because it's a cool souvenir? >

Do you think this way because of scale? Because the regime split was a big event, and a single human deciding to take a piece is small? Is Jim Nobody really insignificant as you suggest? Surely no more or less significant than someone who left their individual handprint on a cave, or who was buried under lava?
History is made of Nobody's. >

It has nothing to do with scale. It has to do with relevance. A caveman leaving a handprint in a cave is history. You leaving a handprint on my car is a nuisance. >

What's the basis of this though? Graffiti in Pompei is history. Newspaper rock is history. How can you know that an imprint in your car will not one day be looked back on in the same way?
A lot of what survives from early settlements are not things that were deliberately preserved - in fact its the opposite, its the buried piles of trash, refuse, broken shards left in the wake of nomadic travel. A lot of the historic record is built from their "trash" which through context became our present historical treasures. >


Graffiti in Pompei is history. Newspaper rock is history. How can you know that an imprint in your car will not one day be looked back on in the same way?

The graffiti in Pompeii was still a nuisance back in that day, I'm unfamiliar with "newspaper rock" are you referring to the Rosetta Stone? 
While a handprint on a car could become a historical item, it's not intrinsically historical if the car was 30 years old and the handprint was 15...sure the print might tell a story, and will give people something to think about hundreds of years after we are gone, but even the graffiti in Rome showed ancient efforts to get rid of some of it. Scuffing someone's car or vandalizing someone's house and using the "Im making a mark on history" is just as good an excuse as defacing a relic from years past, you can ruin a perfectly good book by writing over the words already there, and that's how context and some original intent of things can be lost. 
300 years later they might see a butt print on the hood of a car I'm going to assume that that's a seat for passengers when in reality the person just liked going to drive-in movie theaters and sitting on the front of his car. >

Preserving history isn't about us it is preserving for posterity. Future generations will get to enjoy it. Just because it won't last forever doesn't mean we shouldn't try to preserve these sites. 
Use your argument on climate change. People are part of nature, release of CO2 is how we have evolved to live, the world won't last forever so why try to preserve the environment for the future. >

So what's your answer to this? Why preserve the environment for the future? >

For the same reason people water their flowers in the garden or save old photos for their family. It's just in our nature. 
Imagine we find an old Chicago Streetcar sitting in a scrap yard somewhere. 
If given the option between:
A) The streetcar gets cleaned up as best they can, and becomes part of a Transport Exhibit  in the Museum of Science and Industry for all to see and learn about. 
B) Streetcar continues it's historical journey as a piece of scrap, is eventually is melted down, and likely goes on to become part of something somewhere. 
What do you honestly believe the vast majority would prefer? Personally, I wanna see some trains.
People aren't philosophers. We don't need to trouble ourselves with the reality that we all came from star dust and will eventually return to it. >

So as a “collaborator” I can feel free to damage the statue of David?  According to your logic, with enough “collaboration” there will be nothing left but a pile of rubble.  If someone takes a hammer to your car, would you consider that an act of collaboration with the designer?  Is a brick through a window in your house an act of collaboration with the architect?
I think it’s safe to assume you’ve never actually created anything of your own and are trying to rationalize acts of vandalism.