I think "lying" or "dishonest" is a needlessly strong term. Not all covers are meant to be literal representations of moments or events within the novel. Sometimes they're more symbolic, more an amalgam of elements. For instance, the cover to Only Superhuman
, as seen in my current avatar, doesn't depict any scene that actually happens in the novel, but is more a synthesis of elements from the opening and climactic action sequences. Yet it very nicely captures the flavor and energy of the book and the personality of its heroine.