Returns

Uh, yeah, of course you're sometimes getting someone's returned item. What other option does the dealer have when a mint condition item is returned in like new condition. There's no "law" prohibiting them from re-selling it. If it's damaged, scratched, the box is so beat up that its obvious that it was previously used then the dealer may have to sell it as "B" stock or similar at a discount. When I was in the audio business 30 years ago items that were returned it "like new" condition were re-packed meticulously and put back in inventory. 

The answer is Yes Yes Yes. They wouldn't be able to extend to you free returns if they didn't sell returns as new in the darn box.

No, Music Direct would advertise it as an “open box” or “customer return.” I have purchased these items from them and I can attest that they are great bargains, and you’d never know that they have been opened. Music Direct is a very reputable audio dealer. 

All depends on the company and how they treat their reputation. A quality company will always list as open box and list the condition. My worst case was an online buy from Best Buy. I paid for new went and picked up from store. When I opened the box it was beyond obvious it was a return, no instructions or paperwork and it was very dirty. I took back to store and asked for my money back. They asked no questions and just honored my request.