In most cases I will. Pulling a blob out of a row is a lot faster than opening an additional file handle. There aren't really any downsides to this either unless you are running table scans. SQLite does support indexes (even full-text) and they do work miracles so do use them when necessary.

I would go so far as to argue that SQLite could be used to store all of the assets for any large piece of software (I.e. a AAA game). This would probably wind up faster and more reliable than most alternative solutions out there today.