Let me say what you said back to you, slightly modified, so that you can see more what I was saying above ...
Windy, I can understand some of your thoughts but the fact is when you put down a deposit with intent to purchase you are requiring the seller to take the product off the market. Yes you are compensating the seller for possible lost sales, but more over you are COMMITTING to BUY.
As a buyer, I have an asset called "money" that I have to take off of the market. Maybe I had it invested in stocks, or maybe I had it loaned out to people in bonds, but now I have to take it out of the market and set it aside while negotiating this deal which results in lost revenue, etc, while I have my money sitting there doing nothing. Who is going to compensate me for lost sales i.e. lost interest revenue, lost possibilities to buy another boat, etc ?
Example: I am a seller of boats (lets say a dealer) and you come in to buy my boat. You make an offer and deposit. Another buyer comes along and wants to buy the same boat. I have to turn him down because of your deposit. He buys elsewhere. You back out. I have lost a sale. Your deposit is the sacrafice you made.
I am a buyer of boats (lets call me the buyer) and I go in to buy your boat. I make an offer and we come to an agreement. While we are negotiating, another seller comes along and wants me to buy a different boat. I have to turn him down because we are in a deal. He sells elsewhere. You back out of the deal, and I have lost the opportunity to buy that other boat because I was screwing around with you.
I teach this and proper ways to handle it all the time. I also teach that you want to keep into account the name you may create for yourself depending on the circumstances. There are situations where you keep the deposit or return it. It's the sellers discretion.
If the seller does not live up to their end of the agreement, the deposit has to be returned.
And if the seller does not live up to their end of the agreement it is the buyer who has now lost not only the revenue lost by having their asset (money) "off the market" while the deal goes through, but also the money invested in the survey, the hotel stays for the sea trial, travel expenses, money to haul the boat, and who knows what else ...