Ive often wondered about actual nicotine absorption of pipes vs. cigarettes but its hard to make a comparison given the fact that the nicotine is absorbed differently in pipes than in cigarettes. I think the way its absorbed via cigarettes is way more addictive than pipes. The buccal absorption of pipes, even if its technically more nicotine, is released more slowly and evenly into the bloodstream.
I cant speak for everyone, but in my own experience and also what Ive heard from other light to moderate pipe smokers, nicotine cravings or withdrawals from stopping for several days or even weeks doesn't seem to be a big problem. Can't say that about light or moderate cigarette smokers.
One of the main reasons cigarettes are so addictive is the large proportion of ammonia treated reconstituted tobacco (tobacco scraps turned into paper and shredded) which freebases the nicotine turning it into "crack-nicotine".. That in combination with the instant hit into the lungs and your asking for an addiction.