Hotplug, on boot isn't really hotplugging. That's called coldplugging, loading modules for devices already plugged into the system. If you want to disable it from doing that on boot, first you need to boot up with it enabled, run 'lsmod' as root and write down all the modules loaded. Put them into the MODULES array in your rc.conf file and then remove hotplug from the daemons array. If you've done that correctly you can reboot and everything will work as before