Yes this is sad, but you cannot go around it and the seller usually is not responsible.
For instance I DJed a wedding few weeks back, and the couple would have liked some rock/metallica songs in the mix. So they hooked me up with an iTunes voucher to buy the record, which I did. It sounded terrible and I contacted CS of Apple and they told me they did not master it. So I went out and bought the CD just because at weddings everything should be perfect… put it into my CDJ and -> CRAP. Seems like even a high profile band like metallica can produce utterly bad sounding CDs and nobody worries…. well not my usual genre anyways, but hey…