No, it makes perfect sense. You are correct that it wasn't about punishing rule breakers but about increasing profits. But that's exactly why I said what I did. Follow along:
1)
DCL says you can bring on unlimited alcohol, but it must be consumed in your stateroom.
2) If people follow the rule, then DCL gets revenue from bar sales on the pool deck and in the MDRs.
3) People refuse to follow that rule and take their own mixed drinks to the pool deck and their own glasses of wine (not bottles as to avoid the corkage fee) into the MDRs.
4) DCL loses sales of alcohol to those bringing their own to these locations because people want to drink when they are laying by the pool or eating dinner.
5) DCL decides that since people aren't purchasing their alcohol on the pool deck or in the MDRs, they will place new restrictions. Now no one can have their own liquor-based drinks and must purchase them from DCL whether they want to consume them in their stateroom, on the pool deck, or MDRs.
I have no idea where you are getting the idea that I said this was to punish people.