As a life-career retailer I must take exception to your references. Of course I required stockers to be able to read and match up SKUs, and cashiers to be able to make change without electronics assistance. And let's not forget being able to recognize expiration dates, for both products and coupons.
Yes, being able to read and make change are skills. So is being able to tell time and finding a way to get to work. Most employer require all of that of their employees.
But in a first-world nation, these are skill that virtually everybody else has, too. One needs to bring a specialty skill or knowledge to the job to expect to earn more than minimum wage, and whatever language we choose to use, the issue is about being competitive in the workforce.
This is a semantic problem for you: you object to the word unskilled. I understand. If you want to refer the situation I just described, you'll need to find a term you like better to describe the situation of having little or nothing to offer potential customers or employers and being forced to take low-paying work. Level 1 jobs were suggested. Call these Level 1 jobs if you don't find that term demeaning or offensive.
Unskilled is fine for most people. I've never heard an objection before, but you can't be alone. It's understood that such people actually have skills like those you require of retail employees. Don't take the word too literally. This word in this context means no specialized, marketable skills.
We had a poster recently who objected to the phrase "drinking the Kool-Aid." It offended him (a friend of a friend had died at Jonestown, and he found the expression insensitive), and he was asking for people to stop using it. I said to him what I will say to you - that's an unrealistic expectation.