You are right there are too many fat cats like Square Space, Wix, etc. But SiteCake is nothing like those, in fact I havent been able to finde anything as simple as SiteCake. I dont see SiteCake as a product for the same users of those fat CMS, however I think every webdesigner, webbureau and web-freelancer, should have SiteCake in mind when they design websites. Way too many webdesigner just create Wordpress sites for their clients, when something like Sitecake would have been a much better solution.
If a client just wants to be able to change some text and swap a image now and then, then it is just plain stupid to create a WordPress site, when Sitcake can do that job so better.
Most of my clients dont need a heavy CMS they just need to be able to change text and images from time to time, and with SiteCake I can offer a better, faster and more simple solution for that.