The difference is that in the US, Bachelor's degrees take longer to obtain (4 years vs. 3 in Switzerland) and it's considered the actual 'college degree', while as you know, in CH1 it makes little sense to stop at the Bachelor's level because is has no value except to give you entry to the Master's (with perhaps the exception of ETH/EPF Bachelors in informatics that can lead to direct employment, and professional schools Bachelors, of course, but they're off-topic).
In the US, in general you go to 'grad school' which describes both Master and PhD studies. Masters are sometimes given to graduate students who wish or have to stop after a few years of grad school for a variety of reasons. As a consequence the Master's degree is less common.
To the point: what you learned as a Master students will not necessarily be redundant with first year graduate courses. And if it is, well good for you, you will just cruise through the exams and enjoy having time to concentrate on research instead of studying. Note that, since recently, most (if not all) Swiss PhD programs have courses requirements as well.
On the other hand, you will most of the time have less (or no) teaching assistant work. And there are incredibly good research groups in the US, some will give you the kind of expertise and exposure that you wouldn't get in a Swiss university. I don't think having to repeat a few courses should be a killing criterion if you are interested in a given research environment.
Also, I don't know much about the economics domain, but for engineering, natural sciences and humanities, the actual time to get a PhD in CH tends more towards 4-5 years than 3-4.
1 CH stands for Confoederatio Helvetica, the multilingual abbreviation for Switzerland. I hold a Swiss PhD and I'm a postdoc researcher in the US.