Less than 10% of Chinese people own a passport. Compare this to America (and most other western countries) for example where 40% of people own one.

The number of passport holders is growing rapidly though and as we have seen (even in Korea up until about 2/3 years ago and the THAAD debacle under the previous admin) they love traveling and spending plenty of their money when they do so. Korea being so close should be reaping from this.

Tourism and even business wise which of China and America benefits Korea more..? Being on a decent but not over friendly standing with each of these countries is fine I think.

A smart Korea will play the fool and be both America's and China's puppet really in some ways. Plenty of advantages to this. Choosing one side while turning it's back on the other may appear weak or something but has the biggest payoff I would say as either country (especially China) could crush the country economically.