"them" vs. "those"

Question

In some places, I have found them to be used in a place where it seems to mean as much as those. One example is the song Into the Great Wide Open by Tom Petty. The chorus has the lines

Into the great wide open,
Under them skies of blue

This site already has a question whether using them instead of those is "correct". I am not interested at all in normative debates. Instead, I have a question about the actual use and meaning of this construction, which is not answered in the other question, due to its focus on normative aspects:

Besides the socio-linguistic implications, I wonder whether there are also semantic implications: Does using them instead of those involve a slightly different meaning? Are there semantics, where those and them would not be used interchangeably (even by people who use them as a replacement for those in other situations)?

I have a hypothesis, but I am not at all sure about it. The idea occurred to me that them might be used when the referred amount of objects is very vague and unspecific.

But as a non-native speaker of English, I didn't have the opportunity to study the phenomenon in depth, so I am asking here whether someone has more information and can either confirm or disprove my hypothesis. It goes without saying that if there is a semantic difference, but it is not the one stated in my hypothesis, I would be interested in this as well.

Answer 1

The idea occurred to me that them might be used when the referred amount of objects is very vague and unspecific.

It seems much more likely that this is derived from uses of other plural personal pronouns as determiners. Compare:

1. We workers will be in charge.
2. They will put us workers in charge.
3. You fools never learn.
4. We will never support you fools.
5. I wanted them people to help.

The meanings of such determiners are, of course, derived from those of the corresponding pronouns. Why does this only happen to plural pronouns? I don't know either.

So here's a question: why does "them" as a determiner appear as a subject? I suspect it's because "us" is used in a similar nonstandard way:

1. Us workers will be in charge.
2. Them people will be in charge.

That said, The Yale Grammatical Diversity Project English in North America notes something interesting. You can say "this here book," "these here books," and "that there book," but "those there books" is very rare. However, "them there books" is allowed. This makes it seem like "them" acts a bit more like a demonstrative than one would expect.

Yale also notes that:

[This usage] is widely attested in Appalachian English (AppE), African American English (AAE), and in certain varieties in the Midland and Southern U.S. (Hazen 2011).