As you know, when Earthshaker was first released, it featured a sinking building. There were about 200 of these made, but then this feature was made stationary because of costs. Here's a video of the building sinking during gameplay.
http://vimeo.com/8018914
Also as you know, Farsight buy a real-life table, then copy every part of it exactly. Perhaps they couldn't find one of the original table with the sinking building. But it should be easy for them to adapt a standard one. Then they could make copies which work better. See
http://www.basementarcade.com/arcade/4sale/Earthshaker/index.html
http://vimeo.com/8018914
Also as you know, Farsight buy a real-life table, then copy every part of it exactly. Perhaps they couldn't find one of the original table with the sinking building. But it should be easy for them to adapt a standard one. Then they could make copies which work better. See
http://www.basementarcade.com/arcade/4sale/Earthshaker/index.html