Man, saddens me to see the sharks circling like this for no real reason other than telling stories "about that one time..."
The way I see it Robert is in business, you are not. You want to get rid of something you don't want, he doesn't need what you have (99.999999% of the time). This isn't the same as going to another hobbyist and asking for fair trade even if all you want is store credit. So at the end of the day you are lucky he's going to give you anything for what ultimately is stuff you don't want. He's a business not a charity. Ever try to trade in a car? Yeah you're not getting anywhere close to the actual blue book value on it, ok unfair to compare him to car salesman. Ever buy/sell anything at a flea market or garage sale? Chances are the things for sale were no where close to what the new cost would be, because it's stuff that you/they don't want.
I don't personally know Robert, I've known of him for a long time, and yeah I've met him a couple times when he went to a club event or something, but he's simply not in an area that I frequent often and while not Santa Rosa far, it is far enough for me not to stop by to browse his store on a weekend or anything. But when I absolutely DO need something, I'm damn happy to have a store that isn't a fedex delivery window of 5-7 days away, and when I need a glass tank that is larger than 200 gallons? Guess where I'm going to go? Robert most definitely is one that will be on my radar as someone to talk to, because many companies don't want to deal with the individual customer (like those on a message board), and will I hope for a good deal? absolutely who doesn't? however if his price is too high I'll shop elsewhere and not make a huge deal out of it.
So maybe cut him some slack, a question was asked if they will take frags, simply saying "probably, but don't expect to get top dollar" is all it takes to answer it and be done with it. Just remember, if you can't (or are unwilling) to get anyone in the hobby to buy your stuff, it might say more about what you're trying to sell in the first place.