In the narrowest view, sure. But, for example, not all casinos, hell not even all machines in the same casino, offer the same odds. What about the work you put into determining which machine offers the best outcome? Is that not a skill? Obviously you can just sit down at any old random machine and see what happens, but that's the same as your "zero skill" farmer throwing some uncertified seeds on the ground and hoping for the best. In both cases there is an opportunity to improve your chances of success if you so choose.
Some aspects of farming lean on skill, but other aspects are pure chance. "Pull the lever and wait" is often all you can do. I'm not sure you are being fair in diminishing slot machine playing down to just one event, while happily considering farming as the sum of all its events.
> Some aspects of farming lean on skill, but other aspects are pure chance.
I frequently use this phrase when talking with people about their career path. Replace farming with (office work) career. Mike Bloomberg famously wrote: "Work hard and you might get lucky." I like that phrase because it appreciates the nuance of success.