termcap.db unused?

I was looking at a ktrace dump file recently (/bin/ls) and noticed that
during initialisation, it attempted to read /etc/termcap.db - as that
failed, it then read the text version pointed to by /etc/termcap

Adding a link: /etc/termcap.db -> /usr/share/misc/termcap.db

caused subsequent runs to use the termcap.db version.

Is there any reason why /etc/termcap is linked, whilst /etc/termcap.db
isn't? And if so, what's the purpose of /usr/share/misc/termcap.db ?

Cheers, Jamie