I think footnotes are much heavier in articles in theological circles. Books tend to be kind of light on them, because the author will usually tell you who thought of such-and-such and idea and how the author disagrees with them on some level, and thinks that the interpretations of so-and-so were rather off-base, but would generally like to affirm this particular aspect of blah blah blah. It's a little dense at time, but they are usually pretty interesting, and it means you can follow along with the gist of this particular argument pretty well, even if you cannot yourself respond.