I think the final conflict and subsequent revelation would have carried more weight if I knew more specifically what morals and principals the sisters felt were being threatened by a good meal, and why they were so important. The movie does a very poor job of convincing me their way of living is of any worth; nobody is happy, the congregation is at each others throats, and in general it just looks to be a very oppressive and dreary way to live. I have to assume the real reward is that they have lived a life that will grant them entry to heaven (that's no small reward!) And yet it's never demostrated by the sisters that this is the reason they live the way they live. It's never stated and it's never seen, just assumed (and so I must assume it is important to them).
When the feast comes where's the intensity of the dilemma? They are giving in to to a lifestyle they have denied themselves for their entire lives... a sacrifice they've made for the ultimate reward. You would think that caving on something like that would cause a little more inner turmoil no? Instead they fuss over it like a couple of ninnies. "oh dear, wine". Isn't it more than just wine? In their heads shouldn't the consequences really be life and death? If not, what was the point of all their devoutness? 60 years of piety but who cares when there's quail!
I don't think there's anything inherently silly about living a simple, devout life. I could have easily have been further convinced that it was a very good option if the film had made the case for it. Instead it does the opposite, it sets it up to fail. It makes it look like a ridicules way to live. And in the end when they cast it aside, what are they giving up? Very little. It's an easy choice really.
What should have been a compelling conflict between orthodoxy and, I don't know, puritanism(?) was really a no contest because they pulled a Tonya Harding.