If you agree with Beale's evaluation of Jewish interpreters at Qumran, I suspect it is (1) because you have not taken the time to study the interpretation of Scripture at Qumran carefully or sympathetically and (2) because you agree with the presuppositions shared by the early Christians and reject those shared by the inhabitants of Qumran (commonly identified as Essenes).
Let me explain, taking the second point first. The Pesher Habakkuk commentary from Qumran cave 1 (1QpHab) famously applies Habakkuk 2:2 to the Teacher of Righteousness:
"God told Habakkuk to write down that which would happen to the final generation, but He did not make known to him when time would come to an end. And as for that which He said, That he who reads may read it speedily: interpreted this concerns the Teacher of Righteousness, to whom God made known all the mysteries of the words of His servants the Prophets" (1QpHab vii 1-5; Vermes's translation).In Acts 2:16-21, Peter declares that Joel's prediction of widespread prophesying was fulfilled among the ecstatic tongues-speakers at Pentecost. Like the author of Pesher Habakkuk, Peter assumes that Joel's prediction applies to his own time, which he identifies as the "last days" (Acts 2:17 contrast Joel 3:1). Paul's eschatological take on Scripture is similar:
9 For it is written in the law of Moses, "You shall not muzzle an ox while it is treading out the grain." Is it for oxen that God is concerned? 10 Or does he not speak entirely for our sake? It was indeed written for our sake, for whoever plows should plow in hope and whoever threshes should thresh in hope of a share in the crop. (1 Cor 9:9-10; NRSV)If we believe that the Holy Spirit was poured out on "all flesh" at Pentecost and deny that Habakkuk 2:2 was fulfilled in the Teacher of Righteousness, it is because we share the early Christian assumption that the end of the ages did come with the death and resurrection of Jesus, not because the Essenes were "wild and crazy."
These things happened to them to serve as an example, and they were written down to instruct us, on whom the ends of the ages have come. (1 Cor 10:11; NRSV)
To be sure, Beale's main point was that the contributors to Commentary on the New Testament Use of the Old Testament found remarkable attention to the context of OT passages cited in the NT, and there are passages in the Dead Sea Scrolls where the writers seem to reject the original context entirely. (Pesher Habakkuk is a fine example.)
However, there are also passages in the NT where the original OT context appears to be ignored. In Acts 2:25-32, for instance, Peter seems to exclude the possibility that Psalm 16 ever referred to a situation in the Psalmist's life because "David both died and was buried" and, on Peter's reading, the Psalm clearly refers to the resurrection from the dead. As a result, the Psalm can only apply to Jesus who "was not abandoned to Hades, nor did his flesh see corruption." Most commentators on the Psalms beg to differ. Take, for example, Willem VanGemeren's comments in the evangelical Expositor's Bible Commentary: "The primary significance of the text lies in the confidence of the psalmist that his relationship with God will not end with death."
Now there may well be an explanation that makes sense of Peter's use of Psalm 16 in Acts 2--although all I. Howard Marshall can manage is “Peter’s interpretation in a wide sense in 2:30 is sufficiently plausible” (Commentary on the New Testament Use of the Old Testament, 539). But before calling the Essenes "wild and crazy" we should consider whether there are explanations that can help us make sense of their own exegesis of Scripture. In many cases, such explanations are not hard to find. Certainly, those responsible for the scrolls often interpreted Scripture in an awareness of its literary context.
Much as I appreciate Carson and Beale's accomplishment, and have benefited from Beale's previous work on intertextuality in Revelation, I have to say that calling early Jewish interpreters "wild and crazy" is bad form--even in a popular magazine. Good historians take seriously the golden rule: interpret other traditions as you would like your own tradition to be interpreted.