As a start, need to get more complex from there (probably exclude theonion's About page, for example, but that covers 90% with almost 0 effort -- and standard analogy from there, if Snopes uses 90% of its effort to cover the first 90%, there's no way they can cover the last 10%; if they use 1% effort to cover 90%, there's still a lot of ability to cover the remaining 5% or 9% (because, let's be realistic, 100% is absolutely impossible).
As a start, need to get more complex from there (probably exclude theonion's About page, for example, but that covers 90% with almost 0 effort -- and standard analogy from there, if Snopes uses 90% of its effort to cover the first 90%, there's no way they can cover the last 10%; if they use 1% effort to cover 90%, there's still a lot of ability to cover the remaining 5% or 9% (because, let's be realistic, 100% is absolutely impossible).