Package: dpkg
Version: 1.10.21
Severity: minor
File: /usr/share/man/man8/dpkg-query.8.gz
manpage says: -l | --list package-name-pattern ... List packages
matching given pattern. If no package-name-pattern is
given, list all packages in /var/lib/dpkg/available.
Add an explanation of why
$ dpkg-query -l|wc -l
1553
$ dpkg-query -l \*|wc -l
20720