Yes, page counts can be inflated by use of large margins, font size, wide spacing, etc. and an ebook won't have the same page count as a paper version of the same book. Still, if a store says a paper version of a book is 60, 300, or 1500 pages, that gives me as a potential buyer at least a ball park idea whether it's a novella, regular novel, or the next War & Peace
Not that I would object if they also listed word counts.