Nothing to be perplexed by. (Except, perhaps, that your title does not seem to match your question. )
An EPS exported from within InDesign is not the same thing as an EPS directly exported from PhotoShop. InDesign does not export "the select image"; it exports 'any page item' where its actual contents are inconsequential. ID does not know (nor care) that you only selected a single image.
Unless your workflow is more complicated than you describe, it may be easier to open the original image directly in Photoshop. On a correctly installed system, that can be as painless as right-click image -> select "Edit Original".
Thank you very much Jongware,
This is the confirmation information I was after.
You are right… my question doesn't reflect my post title, sorry about that. My initial question was based on the fact that the exported EPS would yield a transparent background when opened in Photoshop, since the entire page bounds are exported. Originally I included that tidbit of info, then ended up deleting it. Initially I thought the rasterization had something to due to this transparent backaground.
I agree, it's silly why this person was exporting an EPS. Her need (or explanation) was based on limited graphic knowledge. The originating artist has a habit of scaling images within InDesign disproportionately. The woman exporting the EPS just wanted the image by its lonesome scaled the same way as it appeared in InDesign along with the same effective resolution. I told her to export a PDF removing any downsampling, but that seemed to be too many steps for her
Don't use EPS anymore! EPS does NOT support transparency. Exporting to PDF/X4 ist the best way to use it later in Photoshop.