We have first hand knowledge that complainers are tracked with the recent lifetime ban of a couple by RCI.
The problem lies with employees who are willing to use the notes about X passenger in a petty fashion, such as the implications we deleted today that if you do anything which is deemed a "dis" to a cruise ship staffer you will find your entree tampered with or a sudden loss of water in your cabin, or worse.
That type of conduct is completely malicious.
As for upgrades - Lord how sick I am of the obsession some people have with them! And in 99% of the cases, the upgrade is a meaningless change to the same cabin layout on a different deck. I sometimes wish the cruise lines would simply not do them and just tell people upfront - you sail in what you picked. This never-ending quest to get something for nothing really defines the culture we live in.
Personally I've never asked for an free upgrade, and the only ones I've received were those I paid for well before the cruise embarked.
Enough with the upgrade nonsense!