@drVanTraveler — I don't think I've ever been the first owner of any luggage and have never had any problems. Then again, I've bought most of it from either an estate-auction website or a particular thrift sale that benefits a museum and mostly gets donations from museum-benefactor sorts of people.
My guess is that by the time it ends up in an apartment dumpster, any druggies in its history made sure not to let anything go to waste.
I do go over the inside with Lysol spray, though more because other people's dirty underwear than fear of the drug dog, and if it's a softside, treat the outside with Scotchgard. I also vacuum out all the compartments, though all I ever seem to find is dried-up ballpoints and the occasional business card.
In my experience, people are wasteful and will chuck a suitcase because of (often minor!) zipper or wheel issues. Those are easy and tempting things for manufacturers to cheap down, and robust ones are correspondingly a key indicator of the good stuff. If you are willing to lurk and wait, Travelpro costs the same five or ten bucks as the cheap flashy junk...