A good question indeed, Judy. I have often wondered the same thing, and now think it is nothing more than the fashion of the day. As we saw with architecture in the 1960's and 70's, folks went for the "clean" and modern look (read "boxy") for buildings. In the 80's, people regained their senses and began to build with some interesting architectural features. This is seen in housing as well. I think it may also have been a business decision from two different standpoints: a way to attract business by presenting the boats/buildings (and even trains) as "modern". It was also cheaper from a construction and maintenance standpoint. Just fashion swinging from one way to another.