I'm guessing because as he does the retals he'll just get fatter and fatter and then more ppl will grab him. With the building costs now, it's hard to grow your D if you're buying food/oil/jets and building up a ton of land over 25k acres.

Assuming he can afford to build all those acres at once, that retal on herbs12 will take him like 30 turns (very rough estimate, too tired to figure out actual land to build). Add 4 turns doing spy ops w/o failing, 3 turns to grab as a demo. That leaves him with about 15 turns to tech, 1 to sell - not a lot of revenue to do another big retal the next day. So he'd end up retalling every other day and hope no one else grabs him while he's getting fat but not growing his D.

It's a vicious cycle unless he beefs up D a LOT for two days before doing retals.