I don't know why you would apologize for a business decision. Because of the intimate nature of services... well ok... time... provided, people seem to confuse this as some sort of situation where you want to play around, and just HAPPEN to get paid. Advertising notwithstanding, it's a business transaction. Money for time. Just like any other job, and as an independent contractor you can set your rates. Anything else is just an illusion really
The explanation is cool, but people who are shopping for price won't care what the explanation is, and those who don't care about price it won't matter either. To me, it seems a solution that doesn't really address the issue, just quit talking to people when they try to negotiate, that would seem a better way to address it, and more direct.
This would seem more of a move to deter new clients, or people wanting the standard $200/hr Wichita market norm, which might be the point too. It makes you more money to be sure, and that's always a good thing. However, time will tell!
As in all things, the market will determine if that's a good move or not...
Good luck!