VRE or ‘virtual real estate’ is valuable space. It’s a little like actual Real Estate, with less overhead and more potential ROI (return on investment) yet time and time again, the unaware will KILL their Facebook page or other online property!
There are very, very few reasons to eliminate an online property – I can’t even think of one – especially if it’s free! It can lay dormant for now and in the future, it will still be there when you want/need it again.
Such sites can serve many purposes and, as they get older, they gain ‘seasoning’ which can benefit you in search engine results. If the site gains ranking and provides a live link to a more active site, you will get the benefit of a ‘referral’ and sites which get more of these appear more relevant to a search engine.
I urge you to keep those sites! You don’t have to worry about them. Just keep a list of all the sites in your control for a time when it may be useful to you again.