This is a recurring debate and there are pros and cons for both sides.
It usually comes down to whether you need transactional guarantees for
these large objects.
There are also practical concerns. Transfering these large objects
over a single database tcp connection limits the application
performance a lot. And the database is often more heavyweight than you
really want to keep tied up to serve up images.
Also, it makes backups a pain since it's a lot easier to back up a
file system than a database. But that gets back to whether you need
transactional guarantees. The reason it's a pain to back up a database
is precisely because it needs to make those guarantees.