Personally, I'd just use Limitation instead. Like "you have to have eaten this many people in this time frame to have access to these powers" It may not work for all Feeding Dependency, but it's what I'm going to do for Moord Nag, for example.
How much would that limitation worth?
Well, yeah, but I feel like that's sort of the point. It takes more energy to use those powers so it takes more will to avoid feeding if you do. Also, you can always opt not use a particular supernatural ability during a scene if you want to avoid taking the larger hit. (Not going to start an argument about what's better since OP was looking for the alternative; just pointing it out.)
Then again, if you must NOT use a power you bought in order to stay alive, you've done something wrong in character creation. Not to mention, it takes the fun out of the game.
To add to that, it's faster to buy powers, but the skill cap of discipline isn't raised fast enough to protect you when at that high level.
(I am always happy to hear opinions.)