I see your point, truly I do. I'm of the opinion that the drug war is tyrannical, that a person should be able to ingest whatever substance they like based on the principle of self ownership. I also do not believe that SWAT teams should exist in the first place.
However, let's put ALL THAT aside and look at the situation for what it is. You say that surprise cannot be discounted when weapons are involved. Fair enough. But what we have here is a family that is luckily unharmed from a police raid because they decided simply to not even knock on the door. (I would even say magically unharmed given what great tactical talent exists in SWAT teams.) (Sarcasm.) Had they done even an ounce of research involving NO leg work, they should have been able to find that the information they had was stale, given how much the government, even at a local level, knows about you. Say they hadn't, and they went and knocked. This family, innocent mind you, would have answered and said hello and the police would realize they have an informant that is not reliable. What if the family had been injured? What if a baby present in the house was maimed because of a flash bang or some other military grade weapon used? Would we really look back and say "Well the element of surprise is crucial in these bogus drug raids sooo... yea." Damn, I would hope not.