THIS IS THE WORST. A friend of mine used to say "People know the price of everything but the value of nothing." I value that a retailer chooses to stock something I'm interested in and try to buy it if I can. I think "showrooming" is very dishonest to brick and mortar stores. I worked 10 years in bike retail and saw it a lot.
I don't see the correlation though of how the return laws affect music negatively. For as many people that buy something while fully intending on returning it how many more throngs of people take a chance on a piece of equipment that they wouldn't if they couldn't return it and then end up keeping it because it's good gear? I think the generous return laws existing is more of a proof that those take a chance people outnumber the return policy abusers. Return policies are just a numbers decision, as it should be.
Think about all the time you could save sparing yourself from second hand accounts and visualizing the experience of your new gear. As personal as gear is what's better than a penalty-free trial of gear in your own living room showroom where you determine the pace of figuring stuff out?
Also consider that generous returns mean gear manufacturers are beholden to make better, more intuitive, user experience centered products that also need to have depth so someone gets the impression its worth keeping. No more "gotcha" gear that is all marketing and no real substance.