I always have a hard time believing the posters who tell us improbable stories about dickish dealers who refuse to audition equipment unless they’re pre-committing to buy. I’m pretty sure there’s something about them or their approach that makes a dealer who’s paying a lot of rent and day-to-day overhead to sell stuff get standoffish when dealing with them. People very much want to sell you but they don’t want to be treated rudely or be your slave or your dad on a transaction. And as a guy who’s been in customer service to one extent or another my entire life, I guarantee there’s something unreasonable or unsavory about a customer who inspires such a reaction. If you want to be the magnanimous big shot with your money, do all the requisite research, buy the equipment at the most affordable price you can to audition all you like in your special listening room and if you don’t like it you sell it like a desperate hooker to the first guy waving cash in your face.
Wasting someone's time or getting to use their stuff for your purposes will always require a little commitment on your part. That's just a fact of life.