Some of the jobs they listed (like the bartender) are heavily dependent on location, such as in a major city, where the cost of living quickly soaks up the higher pay level.
Some of the others are very varied on the salary.
I also read the WSJ article linked there about the 24 year old making $ 140K/year as a welder. However, he is working 72 hours a week to do it.
Depends on his overall work schedule. A lot of the guys working oilfields and such aren't working 72-80 hour weeks year round, they will work a given duration with a high amount of hours to get a project done and then take time off between jobs. Some of the rig welders I know take anywhere from several weeks to a few months off per year, it's not a 9 to 5 job by any means.
Also the field of welding covers everything from a $10/hr production Mig welder in a factory to high paying jobs like pipe welding in the field or welding special alloys. It's all about skill and experience range.
I know I looked at local cop jobs in 2011 before taking my current job, around here you are lucky to start at 30K
I haven't heard of a flyover country police job that starts much more than around 30k. Same goes for fire.
Hell airline pilots make a shockingly low amount of money (the general public thinks all airline pilots make bank...not so much)