A lot of my posts are without pictures but recently I have started to notice a subtle difference. The posts that I make with picture or that have a decent thumbnail get higher rewards. I am not exactly sure what the reason could be for that but I feel that readers feel that posts with images are more engaging.
And ultimately the idea is to generate user engagement here. So if the images are working then I am all for it. I have using my new smartphone to take a bunch of good images that I can use for my posts (obviously I am not photographer but......)
Well people want to be intrigued, and you want to keep their curiosity, why should they click on your post and then read it. Making a good looking first image is key to getting other users to engage with you.