This is part of the divide and obfuscate approach to climate denialism and the trick is not to vociferously defend glacial melt as proof of anything as that falls into the trap of promoting one single piece of evidence to a "make the case or break the case" status. Instead, let's put these findings in context with other similar findings which when viewed as a whole are impossible to ignore.
No one claims that a few melting glaciers is proof of Global Warming. Proof is a mathematical concept. In climate science one needs to look at the balance of evidence and this is just more evidence on one side of that balance. Widespread and rapid retreat of glaciers is merely yet another observation consistent with all the other kinds of "melting" evidence.
Here is some of that evidence:
Sea ice reaches new record declines:
Glaciers in Greenland are receding and calving at record rates:
This is a global phenomenon:
permafrost is also
Clearly, we are dealing with much more than a few receding glaciers.