We could get rid of the modern marvel of plastic bags, or get rid of the people instead. (I'm not a big fan of eugenics.)
Maybe I'd grow it myself and avoid all packaging and distribution problems, but the climate where I live doesn't support that very well at all and I like having salad during more than one brief period per year. Sustenance farming isn't really one of my goals in life.
And no, I do not think that my want for a salad at a time of my choosing constitutes some kind of unholy elevation of decadence. It's just a salad, and people are allowed to have things.
And the bag, itself, doesn't promote cyclospora outbreaks. It persists on things like greens, but it does not grow on them. That stuff comes from literal shit, like -- you know -- the stuff that everyone makes.