I don't either, but I have the libs installed.
The libs aren't so difficult, but what about the resource requirements? I run a GNOME 1.4 desktop, and as a simple test, I started konqueror to see what resources the KDE infrastructure would use. It seems pretty staggering:
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
...
manly 2162 6.2 1.3 23484 14260 pts/0 S 13:51 0:01 konqueror
manly 2166 0.0 0.7 18876 7876 ? S 13:51 0:00 kdeinit: dcopserv
manly 2168 0.0 0.8 19984 8300 ? S 13:51 0:00 kdeinit: klaunche
manly 2170 0.1 0.8 18920 8416 ? S 13:51 0:00 kdeinit: kded
manly 2172 0.0 0.7 18732 7500 ? S 13:51 0:00 kdeinit: Running.
manly 2173 0.0 0.7 18800 7756 ? S 13:51 0:00 kdeinit: kio_file
manly 2174 0.0 0.1 2512 1588 pts/0 R 13:52 0:00 ps ux
The sixth column, RSS, is the important one. I have plenty of RAM on my system, but even so Mozilla doesn't look so big in comparison.