Spent 3 weeks touring the Oregon coast in September and the zip code thing came up several times. Just did the add the zeros and work each time it asked. I have been in other places previous trips that it didn't work in a few places too.
On the U.S. getting chip cards I have been working on a national project for this stuff for the past year as we have changed our whole POS system in Canada and soon on the U.S. side. I asked several times about chips state side and the feeling is that it won't happen on a global basis. They say it would be too costly to do for the amount of terminals etc. that would be needed to changed and would be an immense amount of cost. It was also mentioned that the feeling is the chips have been out around the world for a long time and the technology is going to change again soon anyways so probably wouldn't be a good idea right now. May as well wait for the next technology wave. Means to me we will be swiping cards state side forever. LOL.