You might say, "Americans would to the work." Right. At $25 an hour, at which point your tomato would cost $7 like it does in Japan.
The reality of life in much of the west is that MOST of the menial labor jobs are done by immigrants, especially illegals. I'd bet that 90% of the restaurant help is illegal, probably 50% of the hotel help, and perhaps the same percentage of gardening landscaping and construction help. I'm not talking unionized bricklayers, but DRY WALL hangers. No matter how you frame it, most Americans will not do that work, and certainly not for $3 an hour (or less, sometimes).
The flip side is, how do you plan to enforce it? Do you really want to jail all (otherwise) legitimate businessmen who, due to the economics, have to hire these people? George Gilder said of Napster, when one person steals your product, you have a theft problem. When a million steal it, you have a marketing problem. When one guy breaks the law, it is a legal issue. When they all do, it is an economic issue, and labor finds a way to a source, no matter what roadblocks you put in place.
There is an alternative. It's called Sweden, where unemployment is about 20% and where no one works more than 20 hours a week because they can't afford to.