This topic comes up from time to time. I am a free market thinker and whatever it brings, it brings, both ways. What I don't like is the constant whine that I sometimes hear from folks who cry they missed something, etc or they get mad b/c it is worth more than when in production and they expect to pay the original price when it consistently sells for 1, 2, 3 or whatever times the original price. Also, how about all of the "can I get a deal pleas" you see. Hey, I don't fault anyone for making an offer, you just have to realize the other person doesn't have to accept it. Just like you can offer a piece for sale, but you might not find a buyer willing to pay your price!
I can only really comment on the way I choose to do things - when I am seeking items, if they are rare and I want it, then I do my best within my means to buy it. I have paid a kingly sum for certain pieces in my collection especially Russian items. That said, I have also paid a kingly sum for original K&C Paper Mache bldgs. I have bought Metal Shed items. I have paid quite handsomely for a K&C Beatles set that originally cost $100. Is it a problem that it has traded between 500 and 1000? No, that is what it is. Point I am making is that it is hard to fault people who are in business, they want to make a profit and they are entitled to make as much as they can. The same can be said for collectors who finance their own collections through the hobby. I do that, it is hit or miss. I have bought somethings at auction that I get my money back, other things 10x , etc. There is no guarantee. For me, the buy/sell and seek/find is all part of the thrill ride of the hobby for me.
One point you also have to remember about dealers and resellers - they are taking a risk. They are putting their capital out there and they have no guarantee at how much return (if any) or how long it is going to take to sell.
And of course, like others I am sure, I have given items away to friends in the hobby, I have also sold items to friends. My rule is if I sell to a good hobby friend, I charge them what I paid. That is sometimes high and sometimes low, but it is a rule I stick by whenever possible and whenever I have memory and records.
Just my 2 cents.
Tom