I think it's a difficult question... Nearly everything we do in western industrialized society relies on the exploitation of resources, whether animal or, as Roger mentions, petroleum products and other less renewable ones–which are of course intrinsic to modern agriculture and farming as well.
{tangent} Industrialized farming is a huge problem, but I do agree with Gavin about plants being just as alive; I personally consider it high human arrogance to assume that animals are more 'valuable' morally because they are physiologically more like us. Industrial animal farming's equivalent in plants is large mono-culture annual plantings: corn, wheat, etc., rather than perennial or re-seeding varieties. But could humanity feed itself without them? Or kill itself by their use? I don't know... {/end tangent}
I personally think that there is no perfect moral place, that we must compromise somewhere, whether we realize it or not, but of course it is better to realize and understand exactly what we are doing and what exactly those choices are that we are making. I don't think digital is any better, with minerals sourced from who-knows-where, including the Congo. Since gelatin is a by-product of an already large scale animal production system, and those bones would be going to waste otherwise, I can see the reasoning in a vegan living with film, with no more than minor discomfort.