Participated in a dig last night before getting ready to run over to Tanis. It turned out to be a research dig so nobody gained any stones for personal use, which was a bummer but not shocking this early in the game.
Digs are an overt example of the kind of social gameplay ATITD strives for. No matter how much of a brick-making badass you are, you're not successfully digging up anything by yourself. You have to get 20 or so people willing to gather and timesink together for an hour or more. Stat-boosting meals and fancy shovels will eventually trim down the number of diggers needed but the basic requirement remains.
Another aspect of ATITD digs is that as they progress, the stones that are unearthed just appear on the ground for anyone to grab. There's thus an organizational side to it as well: designating "diggers" versus "pickers", the latter being those who collect the stones and pool them for distribution at the end.
There's nothing preventing some greedy griefer from grabbing a bunch of stones and running off, but in ATITD that almost never happens. It's partially because of the playerbase, and partially because the drawback for such actions (being known as a griefer and cheat) in a social game like ATITD way outweighs the advantage of getting a few rocks for free.
In T3 beta 2 there was a griefer who stole stones from a dig and also spammed the regional chat. Amazingly enough, there was nothing in place to stop any of this, and the usual social pressure ATITD exerts on its players meant nothing to the griefer.
After about an hour a GM banned them. It was odd to see how a crucial part of gameplay – protecting from griefers – is governed in ATITD by convention as opposed to procedure.