I think you're getting the visas mixed up.

H1 visas are typically for skilled work. Think technology jobs. There capped at low numbers, so they're not as many available as H2.

H2 visas are unskilled labor. Think agriculture, restaurants, cashiers (like your example), etc. We're cranking out H2 visas like there's no tomorrow.

I'm not trying to be contrary, but it's important to know the difference and use them correctly because we deal with them differently.

For instance, many skilled US workers are furious over H1 visas, because the jobs involved in those are highly sought after and often pay $100,000s per year.

While H2 visas are for drudge work and pay peanuts and are avoided by legal US workers so much (at the rates those jobs want to pay their workers) that there's a huge labor shortage and we can't get foreigners over here fast enough to fill them.

They're not filled with university graduates now, because most university graduates aren't going to do that drudge work for $8/hr.

Our government keeps LOWERING the minimum wages that companies can pay visa workers, thus increasing the demand for visa workers.

If a business could only find legal US workers who would do the work offered for say...$15/hr, but could import foreigners who could do it for $8/hr, which do you think they're going to employ?

These aren't difficult jobs. Trained monkeys could do the majority of them. Why would they willingly pay a premium to hire people for these types of jobs?