I disagree for another reason. Have access to the code allows easy comparison. I did some research in grad school on a computational method and there was a known best implementation that was in the research. I reached out to the author and he kindly supplied me with the source code of his work. I wasn't trying to replicate his results, but rather I wanted to compare his results to my implementations results in a variety of scenarios to see if I had improved over the other method.

And to the original author's credit, when I sent him a draft of my paper and code, he loved how such a simple approach outperformed his. I always felt that was the spirit of collaboration in science. If he hadn't supplied his code, I really would never have known how they performed unless I also fully implemented the other solution -- which really wasn't the point of the research at all.