/snap directory is the customary location where installed snap packages are presented to the system.
Used disk space.
While a file manager will show many files and directories taking up space this is a subtle illusion. The actual contents contents of those files is stored in
/var/lib/snapd/snaps and it is heavily compressed. You may think of an analogy of looking at the files present on a CD-ROM disk image. You can see individual files and directories even though the disk image is in one big file. Snaps are similar to such disk images, they just use a different file format that is optimized for read-only data and not for a spinning disk.