You can't blame his friend for trying though.

Actually, I can see how he should expect to pay less for a full cord of 24" wood though. The major producers around here all have processors, so the extra weight shouldn't be such an issue.
The "cord" measurement was originally defined for woodcutters who were cutting pulp all week for wages.
Firewood is the least valuable wood product produced, yet still falls under weights and measures. (It's also the wood product which generates the most complaints from buyers.) If you deliver a "full cord" which turns out to be variable lengths, you could very well get a visit from the weights and measures department.
A few years ago my cousin asked me about a load of wood he bought; 4 cords of 8 foot firewood, neatly stacked. Every stick was 90".
I don't know if he actually did anything about it, but suggested that he talk to the producer and get a price reduction.
Another term used is "thrown cord"; the legal definition of this is an unstacked pile, and a cord is 180 cubic feet.