Suppose that I am reading a marketing book and, while reading a specific chapter, I find like there are 10 footnotes with most of them related to specific examples or specific numbers; in other words, most of the information presented in the chapter are not cited and, judging by the context and contents, such information do not appear to be 'invented' by the author(s) of the book (not primary data). In that case, they could just be common knowledge information related to the field of marketing and business (example: purpose of marketing, strategic analysis, financial measures, etc...)
Since 'when in doubt, always cite', if I want to write about information taken from such book, is it bad if I just cite the author(s) of the book since I am taken the information from their book? To clarify, I am worried that I could be 'giving credit' to people who did NOT come up with such information presented in their book and therefore, I should not cite since it's common knowledge or whatever.