JMich: Having a piece of equipment remain static despite the movement of the vehicle it's in is relatively easy, but the CD anti-skip technology needed a larger buffer (still at a small enough package) and faster reading speed.
F4LL0UT: That's kinda paradox. The problem with skipping CDs was also a mechanical one and theoretically it could have been solved mechanically but obviously "having a piece of equipment remain static" must have been more complicated and/or expensive than adding the buffer.
Having a CD and the laser be static is much harder than having a vinyl record and the needle being static, especially due to the rotation speed (and margin of error). A small movement of the vinyl needle may not remove it from the record's groove, but the same movement on the laser will make it move to another CD "groove".
And from what I saw in the Highway Hi Fi, the vinyl was held in place with a central pin, but few CD audio equipment had that option.