Does anyone use wood for vibration control?

The entire building is vibrating. So, even if there were a material that didn’t vibrate much the component on the rack or platform would still be vibrating, right long with the entire building. Thus, the theory that wood is no good because it vibrates doesn’t hold water. The trick, gentle readers, is to decouple (isolate) the component from the building AND use very hard cone materials, I.e., not wood or carbon fiber or even brass, underneath both the component and the iso device to allow “residual vibration” to rapidly exit stage left. Cryogenically treated heat tempered steel would be a good place to start.

Sound is nothing but vibration within the bandwidth of the ear. So, you want materials that don't resonate at those frequencies.  

Hell the Earth is constantly vibrating and ringing from earthquakes etc. It’s a matter of degrees really. It seems all of audio is managing vibrations.

Mapleshade’s footers are not cone shaped because cone tips can resonate at the wrong frequencies. They are cylinder shaped with a shallow point instead.
You will get lots of opinions on this as with most topics. This comes down to tweeks really. In the grand scheme of audio things it is better to get the bigger issues of equipment synergy and the room/speaker setup dialed in before worrying to much about fine tuning with racks and cone and such. The exception being for turntables. Very important to have a good support under a TT.

If woods didn’t resonate they wouldn’t make such good resonators, you know, like the Mpingo disc.

She wouldn't need the vibration if she had the wood.