The extra Force Point sounds good as a reward for draining soup, but giving the character XP for it makes it too easy for a character to level up while the +1 to stat could make the character very powerful very quickly and could unbalance the game. As I understand the Anzati, the penalties for not consuming soup is that the creature is subjected to an overwhelming urge to seek it out, he becomes weaker (-2 to STR and CON for every level) and will eventually die if he does not suck soup. I like the idea of the opposed STR checks for overpowering/incapasitating prey and the ability to make a CHA based roll to "charm" their victim. Similar to how a vampire seduces its chosen prey. Perhaps a species bonus skill "charm"?