Typically, when House Wrap is mentioned, it's used in the context of air-infiltration-barrier. It's NOT a moisture barrier. DO understand that a house still needs to 'breathe'. If it's too tight, you might as well live in a jar.
Depending on the environmental conditions in which the house is situated, or even the materials used, one might or might not use a House Wrap. If it's being used, or not being used, as your builder why, or why he's not, using it. YOu can insist one way or the other and see how he reacts. My best to ya and hope this helps.
PS: Shore homes would be a good use for Tyvek; not log cabins.