It's probably been thought of and accounted for already, but I have to ask: could the government first amend the constitution to remove Article 79, and then start messing with the parts it protected? :).
From what I know, the current legal consensus is that this is not possible (despite not being explicitly mentioned, which really seems like a strange oversight, but it's seen as being obviously the intent of article 79) – the only way to get rid of it would be to replace the Grundgesetz with a new constitution. (Some argue that since the institutions that could replace it are bound by the Grundgesetz, them enacting a constitution that doesn't provide the protections of article 1-20 would not be legal, but that's further in the realm of untested theories)
And of course, changes like this would be likely to happen in political environments that don't care about these things.
Article 79 does not overtly protect itself in the literal text, but constitutional scholars are pretty much unanimous in their assessment that Article 79 is indeed included, because any other interpretation would render Article 79 pretty much useless.
(Teleological interpretation)
There is also Article 20, saying in part: "The Federal Republic of Germany is a democratic and social federal state.
So the social obligation of property isn't a fluke, but more a consequence of this provision.
The "social" is really important here and it is being interpreted as a real duty of the state to achieve social welfare. And it is so central to our constitution that it is protected by the "eternity clause" in Article 79:
"Amendments to this Basic Law affecting the division of the Federation into Länder, their participation on principle in the legislative process, or the principles laid down in Articles 1 and 20 shall be inadmissible."