While holding shift, or crouching if its bound differently, will break the plant and give it to you instead of the crop. Not sure if this is a bug but cant find anywhere where this is a feature listed so figure I would say something here.

Maybe a feature? Shift is commonly used to revert the uses of stuff, especially in mods. (Example: Optifine Shaders options can be long can be gone backwards by holding shift)

yep it is a feature :)

This is correct, it's a feature.