Well, one value is protecting the innocent from grave harm. Another value is knowing whether you are actually receiving the Body and Blood of Christ -- or not. 

I think a lot of people would say that *both* of these are rather important, because the Eucharist is, after all, the "source and summit" of the Christian life (Vatican II) -- so getting the Eucharist right would matter quite a lot.

To some of us, at least.