As we cruise the same ships and same cruise line often (and the crew moves around from ship to ship), we do tip "more than expected" and more people than the bare miniumum dining/room stewrds. etc.
The service we receive is fabulous and they remember us from cruise to cruise. It is highly likely we will see many of the dining stewards, bar stewards, deck stewards etc again and we want them to know we appreciate the "little extra" effort they expend on our behalf. It does greatly enhance our vacation and we're glad to say thank you.
But...why should that alarm someone else? We certainly don't run around the ship announcing the details of our tipping habits and have no particular interest in what anyone else saw fit to extend to the crew as thanks.
If you only go to a bar once in a ten day cruise, you wouldn't be apt to tip the bartender (and he wouldn't expect you to) but, if like us, you are there every evening before dinner, you probably would WANT to tip him...at least we do.
Do what you wish....but your fellow pax should also have the same "right" to do as they wish.