I believe in transparency since I'm in the same line of work, and since you didn't really respond to my initial question, I'll clarify to everyone.
Your sites are based off of pre-existing themes/frameworks. These are not custom designs. (Example - here's the rachelcapone site's theme: http://theme.co/x/demo/integrity/4/
(wfs)). There is nothing wrong with these necessarily, but you should be honest with people with the work that you're doing and how you're able to do a site in two days as you say.
There is definitely money to be saved with going this route for some clients. However, in my experience, a lot of gym owners have absolutely no knowledge or desire to do much more than login and post workouts. Wordpress is made so admins can easily change things around without needing to invoice a developer such as yourself. The caveat is that is has to be built correctly to make this easy. My experience with packages themes is that they offer so much flexibility and options that it is overwhelming and more confusing for the admin.
So anyways, just clarifying to everyone the service that you're offering. Not saying it's good or bad, just making it clear.