Hi Mark,
The reason this is happening is because you may have your featured images set to show up automatically in your Genesis Theme Settings.
In your admin, go to “Genesis Theme Settings”, then click the “Singular Content” tab. From there you’ll see the options to turn on or off Featured Images from showing on Posts or Pages.
If you would like to leave that option turned on so the featured images continue showing automatically for your Posts or Pages, then you can individually turn them off in the Page/Post Editor itself.
To do this, go to the page you’re editing (Homepage in this case). Click the Genesis Icon on the top right (G logo) and check the box that says “Hide Featured Image”. This will turn it off for that particular page.
Let me know if this helps.