Well, a couple of things. I am a bit dyslexic, and I was writing about 32ga pins, not 23ga, so let me set that straight.
I got curious, and when running errands, went back to Lumber Liquidators. The packages clearly say BRASS, 32ga PIN. 3/4" was 2.99 a box and 1" was $3.99, so since I use 1" more often, I got a box of those. 6000 ct in either box. All the boxes were sealed shut.
When I got home, it was clear that they were brass colored steel. They are magnetic. I did not test to see if they were galvanized, but I might later.
With two 3/4" MDF scraps I tested how they drove into MDF. I am not sure if MDF is near the density of a material like red oak, but I figure it is more dense than dimensional lumber scraps. About 100 pins were driven, and they worked well.
When in the area, I will now pick up a box of 3/4" pins. By then I probably have tested to see if there is zinc on these, and hence whether they are galvanized.
Actually, it was a good purchase, because I usually pay much more for 6000 pins...and unlike the last box I bought, these were full strips, not busted up strips with 10 or less pins per segment (grumble).
Poor labeling, and me wondering if they were something special, which they are not.