@Mocha. It's very very simple. There are hotter and younger escorts on the market. Clients contact you as a Plan B option when they try to book escorts that they want. If it works out with them, you are the one who is getting tossed.
Also, another reason. That attitude that you display in your original post, may impact how you communicate with clients via texts. If a client senses it, they may chat with you for a while, but would not meet.
The option with "pay to plan" may work with a couple of clients a year. If you are ok with this traffic, go for it.