I'm pretty sure you draw the same line:
* Pealing a carrot: not cruel
* Skinning a rabbit alive: unnecessarily cruel
For all the nonsense about plants experiencing "pain", they, uh, don't. Animals do. Outside of bad philosophical arguments, everyone behaves broadly in accordance with that belief.
I certainly behave as though plants do not experience pain.
However: plants are only noticeably animate in time-lapse footage, and have no mouth with which to scream.
I have no idea why the particular electrochemical properties of the neurotransmitter exchange membranes in my body are able to give rise to qualia, so without that I can't rule out plants doing that but very slowly.
Of course, if they do, then my skin may have an independent qualia to my kidneys let alone to what I call "me", so as you say, I don't live my life as if it were so.
Yep, my argument isn’t grounded in whether a carrot feels pain — the comparison is to underscore the idea that in each case a living thing is extinguished from the world, and that they’re equivalent contrary to metrics like pain or “more like us”, simply for having experience.