On a 'not too long ago' cruise of four weeks duration more than 40% of passengers did not pay the prescribed tips, they in fact paid nothing. Information came from the staff purser on the ship.
So for one whole month the servers on the ship only got 60%of their normal tips wages.
This is a good reason for tips to be included, or to make people pay up front before the cruise takes place.
I have a feeling because this is happening more often that the cruise lines will change their policies is some way.
I also think it is up to the individual whether they pay the tips or not. It's not up to other people to decide for them... whether it's the right thing to do or not is an opinion and everyones opinions differ. Doesn't mean you will change their outlook on tipping.
I hate tipping and I don't care in the least whether others do it or not, it's really none of my business or anyone elses for that matter.
BTW 70% of the passengers on the above cruise were from the US.... says a lot about what they think of tipping too. I'm thinking there must be an awful lot of forum readers who don't pay tips out there but haven't got the guts like TR to post.