Wood blocks underneath components?? snake oil?

If you go on to the Cardas.com website to read about the Cardas Myrtlewood Golden Cuboids, the basis for this product introduction is explained. It is hidden in the "accesories" section.
Ayre has these labelled for them, I believe.
Basically, vibration absorbing, and an apparent tuning effect, combine to improve performance. Works well where I have placed them, but no single brand of reasonably priced footer is "perfect" for every component, so you have to listen when trying the myriad of footer choices out there.
The Cardas Myrtlewood Golden Cuboids (the rather Biblical sounding name kind of gets you in the mood to hear better performance, don't you think?) are inexpensive, don't add any instability to the supported component, and do not add much height, compared to the original equipment feet.
There are now very many support products competing to create the best support for a given item. If you never try any variations in component support, then you may never "miss" them, but fascinating to hear differences, if that is a part of the audio hobby you might enjoy.

Another vote for Herbie's Tenderfeet, which are low cost, and can be tried at home with money back guarantee. Seem to work wonderfully on a variety of underlying surfaces, wood, marble, granite.
After trying wood blocks, I have ended up using them on top of certain components to subtly tune sound, and as mini-bases for the famous Star Sound Audiopoints, with and without the additional subtle tuning effect of an intermediate Audiopoint Coupling Base between the point and the wood.
If the basic "sound" of a component is enjoyed then the very simplest idea is to try Herbie's Tenderfeet, first. A lot of what many seek in their system's sound is unveiled, or allowed to happen, with these relative bargains in support.
Herbie's also has many variations to interact with, or modify, their basic Tenderfoot product, and to interact with other manufacturers' products.
Using the plain vanilla Herbie's Tenderfeet is probably the most cost effective way to get started with great "universal" component support. The home trial offer allows one to hear in his/her own listening room before making a final decision.