How to manage auto created image sizes in Parallax Frame

I noticed the theme, Parallax Frame, is creating multiple sizes of each image I upload to my site. Sometimes as many as 9 copies are present for each image. I have a portfolio site so I post a lot of relatively large images, so this is a problem. I wondered if it's necessary for every image to have so many sizes? Can it be set up so only the Featured image has this behavior? Can I set all the WordPress created media sizes to 0 so It creates no extra images without causing potential problems if I change the theme in the future? Does the Pro version have any extra options to manage this issue? Can the Functions or Core files be modified to change this behavior? Just trying to get a grip on this. 7 or 8 versions of a headshot or something within a post seems excessive and is bloating my DB and server usages. My site is http://www.CreatedbyCrosby.com. Thanks.