Don't underestimate the l33t ph4rm1ng sk1llz... even if you're doing everything by hydroponics, you still need someone to say 'The crop is ripe' or 'That don't smell right'. And anyway, the average farmer (in New Zealand, at least) is a one-man expert in finance, vetinary medicine, multispecies nutrition, birth assistance, ecological planning, heavy machinery operation, cooking, labour force management, etc etc etc.
Damn it, with people like that around, I'll never get to Mars!
ahem
I really don't know if I'd want to go to Mars. It depends on the time frame. Am I a pioneer, likely to spend the rest of my life in a small dome poking at rocks? Probably not; I wouldn't be too useful to such an expedition. Am I am immigrant, going there to enjoy the culture and stuff? Probably yes; I think it would be cool.