I understand there are some features to Jobslingerplus that could be especially useful if you needed to change your email address, phone etc. or sign up with all SASSIE companies as you can do global changes, additions. I am saving my 'free trial' for some time when I need to make such changes.
Not deleting shops is actually a benefit to shoppers who don't/haven't checked the site in a while. They allow you to see what jobs WERE available and so are likely to reappear in the future so you know you are signed up with appropriate companies. If I rush in and grab a self assign off a SASSIE site job board and you come in the next day, you will never know that the job ever existed.