More amateur psychology.
Bills Gates is an example of someone who thought that they had never paid for sex their whole life, then getting a huge invoice for services rendered. He's not unique - anyone that gets married without a prenup in the USA is putting themselves in the same position.
Of course you don't have a 100% close rate. Nobody does. You win some, you lose some of course. But you pay every time, whether you win or you lose. So multiply your cost per date by 3 or 4 or whatever, then add the cost of acquiring the lead.
You enjoy spending your time and money doing this? Well, good for you. Like I said earlier, what matters is whether you enjoy the experiences you have and whether you feel like you are getting value for the time and money spent.