I am speaking from 30+ years of experience in cruising (35+ cruises) and smuggling booze on board.
When I first started cruising, I could barely afford the cruise, let alone a corkage fee. I would routinely smuggle on board rum, vodka and wine. Never got caught. Never felt bad about it. I justified it to myself by saying the cruise line is still making a profit on me.
Eventually, I could afford cocktails in the bar and stopped smuggling booze. I still brought wine, because we were often gifted wine, pre-cruise by travel agents and hotel managers. Back then, you could bring aboard wine for room consumption at no charge. There was a corkage charge in the restaurant. However, I was never charged because when I brought wine into the restaurant at night, I told the waiter/sommelier I would be "most appreciative" if he could open our wine for us. That meant he got a nice tip and he/she never charged corkage.
Now I'm retired, comfortable enough to order the higher end wines that are not included with wine packages. I still am " most apprecitive" the first few nights with additional gratuity. Service is always excellent.
My point in all this is every passenger has a different reason for what he/she does to get the most out of cruising. Let's not criticize each other.