A good few years ago I bought a book from a respected British publisher that specialised in craft books. The book had glaring mistakes in it, including a missing diagram, inaccurate patterns and mistakes in the text. I wrote to the publisher and included my drawing of the diagram that was missing, plus notes on all the mistakes. I asked for the job of proof reader, reasoning that if they already had one, then they weren't up to the job and I could do it better!
You could have knocked me down with a feather when they replied that they didn't have a proof reader, and that they would be delighted if I would do the job. They offered a set amount for each book, and I took on the work.
But I did have various problems with the company. Provided they sent me the roughly typed copy of a book, and I found mistakes, they would correct them. But if they were late sending me copy, in other words, if it was already typeset and almost ready to print, they rarely corrected them, reasoning that it was too expensive at that stage to do so. I used to get cross with this situation - I told them that I couldn't see the point of employing me if they were prepared to ignore my advice, and publish with mistakes that they knew about. In the end, I resigned from frustration. About 18 months later, the company was sold and they now trade under a different name.
So yes, I would write to the publishers of your book and tell them about your concerns. If no one points these things out, they will never know, and it could be that the cover pics were chosen by an editor that doesn't necessarily have any knowledge of the craft involved.