In this case, it doesn't especially matter who actually said it. It just happens to be true.
But on that line, someone elsewhere talked abut "The demise of the canonical text" on the Internet. How do you know that the copy you are reading online is a true bitwise copy of the original? You don't know, and you probably can't know.
I always have a 10lb sack of virtual salt handy when I read online. Much of what I see requires many grains of it...
Training? From the viewpoint of most Radio Shack outlets, they are a retail store. Salaries are a major part of brick-and-mortar retail costs. They want to pay minimum wage, and the requirements are being able to work the register and maybe to have an idea of whether something is actually in stock. Actuially knowing something about what they sell comes from working there a while, maybe.
I'll go to Radio Shack to get tools and adapters. I will assume no knowledge on the part of the staff. It's on me to know what I'm buying and whether they in fact have what I need.