Honestly wtf does the glue matter when people are going through plastic like it's nothing? Bringing up the glue is such a weird nitpick.
Do this thing: 10 pounds of filament poop still exists, + 8 pounds of glue sticks (which is basically a thermoplastic) used, to create something that's eventually going to end up in a landfill.
Are you being deliberately obtuse?
Recycling or reuse is not as useful as just not creating waste in the first place.
Let’s say every month the artist repurposes the last pile of plastic with more glue. At the end of one year, the 10lbs would turn into 1100lbs. At the end of two years the original 10lbs would have turned into 1.3 million lbs of plastic waste. Surely that would frame a very powerful message about plastic waste and green washing misleading public policy.
Reuse is good if the activity replaces something that would generate more waste. This is the real benchmark, not the case where someone does nothing.
The most efficient thing is always to do nothing and/or kill oneself. This isnt practical, so reusing used materials instead of new when you do something is still net good.