One theory: Cause big tits are the most obvious physical sign of feminine fecundity. Before people wore lots of clothes or bras, and before modern plastic surgery, big full tits were an obvious sign of femininity and likely reproductive potential. Grug likes big tits cause it means Grug's partner is a real fecund woman, not a man (fat man moobs aren't shaped like big young woman tits), boy, prepubescent girl (no tits), or old lady (saggy tits), who he can't procreate with. <|endoftext|> A big tiddy thread on this board of all places?