This is a tricky issue.

In a logical, real-world setting, there would absolutely be deaths caused by the Hulk's rampages. After all, he has been responsible for billions of dollars in property damage. Can we really believe that not a single person was killed in a Hulk-related disaster?

The (apparently non-canon) story, Startling Stories: Banner dealt head-on with this idea, as I recall.

However, despite the realism of the notion, saying that the Hulk is a killer drags the Hulk's world--and, by extension, the Marvel Universe--into an uneasy moral setting. 

And, fortunately, comics are not the "real world". The stories may ideally take place in the world outside our window, but in cases like this, the rules have to be bent.

After all, the Hulk, despite being an antisocial brute, is still the protagonist of his book. He is not a villain, and is not inherently evil. And Bruce Banner is a heroic character, an ordinary man cursed to become a monster as the result of saving a stranger's life. And I've never really subscribed to the idea that Banner is good while the Hulk is evil. Banner clearly has an influence on the Hulk, and the Hulk has also been said to be a twisted reflection of Banner. Banner is not a killer, and so, deep down, neither is the Hulk (as the pilot for the 70s Hulk tv series explained very effectively).

If the Hulk "really" was a killer, Banner (at least the Banner I know and love) would rather die himself than risk any other lives.

So, here's my take on the matter: It may be "realistic" for the Hulk to leave a trail of bodies in his wake, but for the sake of proper characterization--and the moral/social/emotional identification of his readers, the Hulk must not be a killer.

Even if it's totally illogical and unrealistic.

Because if he is a killer (intentional or not), then he should be labeled as a villain, and not be promoted by M***** as a "superhero" character (although that adjective is also somewhat incorrect). Despite his antisocial tendencies, the Hulk has almost always been portrayed as a sympathetic character. He's strong, angry, and misunderstood, but he usually lashes out at the right targets (like supervillains and alien monsters). His rampages allow readers to blow off steam without opening up a sticky can of worms (in the form of the inevitable moral implications of the deaths that would and should be caused by those rampages of his).