I'm not sure sharing code is such a great idea. If you use the other guy's code, you might be replicating the other guy's mistakes. And having the code available encourages that.

It would be better to describe your methods, so someone else can implement it in their preferred tools. If they still replicate your results, that strikes me as being much stronger than just rerunning the same, possibly buggy, code.

I mean, if you're working with monkeys, other scientists can't reuse your monkey. They have to follow the procedures you describe on their own animals.

Another issue is that the code might not be very useful to other labs as-is. The code might be for unique, custom-made hardware, or an unusual configuration of equipment, or in an unusual language.