I grew up front-only too. When my wife and I got our first apartment together, we tried front and back for a bit but it didn’t do anything noticeable so we just do front. Like you said, since it’s a bag it compresses easily. If it were a hard plastic for some reason, that would be a different story. I know there’s a strong discourse on it but after trying both sides, I’m a firm believer in the front-only technique.