"Size" vs. "Size on Disk"

[TeeeBear]

The C:\Users\MediaStreamingAdmin\AppData\Local\Microsoft folder shows 2.98gb size, but 11.4gb size on disk. Within the folder (with hidden files turned on) there are two more folders; "Caches" and "GameExplorer" which both appear to be empty, and one 256kb .dat file. Can anyone explain what's going on? 

 

This is a 60gb SSD with only 6gb available so I'm getting low disk space errors. The other day, I had removed some things and was up to ~15gb available, now all of a sudden I'm back to low disk space again. :/