Laserdisc doesn't have a bitrate, so that is a bit of a mixed statement. Laserdisc doesn't suffer from MPEG artifacts, but seriously, an anamorphic well encoded DVD will beat an NTSC letterbox laserdisc unless there is something seriously seriously wrong with the DVD encode.
The audio isn't necessarily of higher quality either - many Laserdiscs and DVDs have the identical 5.1 soundtrack, bit for bit.
The reason *some* laserdiscs sound better (in 5.1) is that there was sometimes a different mix for the laserdisc and the DVD, and the DVD one was compromised to get a mix that would still sound 'good' when mixed back down to stereo or mono. ("Heat" is a good example of such a disc - the laserdisc has a much much better sound mix).
On your other statement re current bootlegs, and people not coming after them - I won't comment except to say I disagree.
The movie houses are getting more and more litigious, it is harder to go after copies of Laserdiscs because they had no form of 'copy protection' to break, so it is only the copyright breach (unlike DVDs which get covered by the DMCA in the US which makes it a crime to circumvent copy protection) but there is nothing to stop them coming after anyone, even after a long period of time.