In addition to storing tags in .git/refs/tags, git also stores tags in another
file, .git/packed-refs. The packed-refs file is used when projects have a
large number of branches and tags, as keeping them in one file is
fafter.

From what I can tell, unless it is specifically asked to do otherwise, git will
place newly created tags in the tags folder and place fetched tags in the
packed-refs file.