Okay, case in point: PMD shows cute, smiling little Pokemon wearing what look to be bibs or do-rags around their necks. The main Pokemon series games (Yellow excepted) feature badass looking legendary Pokemon (or fully evolved starters in the case of the Kanto games) on their covers.
And I did play a 5 minute demo of PMD in GameStop that left me wanting to get those wasted 5 minutes of my life back. I seem to remember the battle system being atrocious. I don't recall what about it was atrocious, just that it left a very bad impression on me. Then there's the whole "no trainers" thing but I did go into GameStop that day years ago knowing that, and did give it the 'ol college try... and regretted it.
But anyway, what's wrong with judging books by their covers? I do it all the time. My recently acquired book that said, "Hilton Head Island Visitors' Guide" on the cover did, indeed, contain visitor information for Hilton Head Island inside :P