We spent 2 weeks on P&O Arvia last September without a drink package and I was shocked that we'd spent £330 on drinks. I wouldn't (and won't) in the future buy a package as we don't drink anywhere near enough to justify it. £100 a day over 2 weeks? That's £1,400 on alcohol which would pay for another cruise! Each to their own but I'd rather have another trip than booze.
You're right, a drinks package on a longer cruise can seem like a bit of a hefty investment. The longer cruises we've done (and booked for the future) have either had included drinks, or really good deals on a drinks package. And we would probably make the same choice.
P&O do seem to be the most lenient of everyone with bringing drinks onboard. Will definitely bring bottled water again next time we travel with them, but I dont think we'll drink much alcohol in our cabin, would much rather be out in one of the bars
Apologies if you're not a fan of watching people drinking on holidays, as a lot of our content does show that. We do enjoy a drink or 2 whilst on holiday, particularly on a cruise, and love getting around all the different bars onboard. However, our everyday lifestyle is nothing like this, so I think it balances out fine.