People are more sensitive about killing lobsters than other animals. This likely has much to do with the more personal, face-to-face experience we have had at some point so near to the end their lives.
It’s hard not to cringe when witnessing a lobster placed in a vat of boiling water if you have the understanding they experience pain like we do. Lobsters, in fact, don’t have the same central nervous systems most humans erroneously expect.
Incapable of experiencing sensation like mankind, the way lobsters perceive the world around them is comparable to that of an insect. Only capable of detecting sudden stimulus, they can’t process the pain accompanying placement into boiling water the way a person would.
Though the traditional means of cooking lobster- dropping it into a pot of boiling water- is much more humane than most realize- there are options better suited for those more sensitive to the concept. You can slowly and much more quietly kill the lobster in either fresh cold water or chilling it in the freezer (without freezing it) before cooking. These options effectively put the lobster to sleep.
When you practice slower death techniques, however, don’t expect the ‘screaming’ to stop. This sound is inevitable when cooking lobster in boiling water, as it’s actually the sound of steam escaping the creature’s shell and not the sound of an animal writhing in pain.