and not spending more $?
There may be, but it depends on exactly what it’s going used for. Each token, bit of contract data, vote, and everything else that has exists on the blockchain uses up RAM until that data is removed.
There unfortunately is not really an easy way to look at this data from what I can see. There used to be on block explorers sections where you could see what was using your RAM, but I can’t seem to find one that’s working at the moment