Interesting thread, some facts I would like to throw in here:
Regarding splitting commissions, it is explicitly forbidden. The risk is too great to be found out as the punishment is having your links taken away.
Most bloggers started this as a hobby. Some have managed to make it a huge business.
It is the responsibility of each blog reader to reward good blogging practices and blogs that ADD value to them.
Most blogs quit due to life changes and/or not getting enough support from readers.
When you post on the internet you will attract trolls/haters. If you do not have a thick head you should not become a blogger.
In my blog I review miles and points blogs. I keep a list of blogs I love, like and ignore. Many of the blogs the OP mentioned are in the Ignore list. ...! But hey, if they add value to you please support them.
This is not a hobby anymore. This hobby thrives in being under the radar. And the airline/hotel industry is incredibly different from many years ago. Commercial blogs are a HUGE reason for the hobby slowly disappearing...This will reverse when most blogs quit when the banks stop paying fat commissions to keep selling credit cards to newbies----->people who never had a travel rewards credit card before and are probably not suited to managing credit responsibly...
I could go on...