Not crazy at all. Plenty of liveaboards include drinks or at least beer and wine in the fare. But, as already noted, Cozumel Palace is the only resort on Cozumel that includes both.
That said, except for the extra cost in addition to your all-inclusive room/food/drink package, there's no need to use the onsite dive op at any Cozumel resort. Many dive ops in Cozumel will pick you up from the resort dock so that the effect is the same as staying at a dive resort. Even better, they store your gear for you so there's no need to take it to and from the dive boat each day (though be aware that some dive ops will not store your wetsuit, which sort of defeats the purpose of gear storage IMO).
Besides Cozumel Palace, where you can use the onsite Aqua Safari dive shop using the resort credits that come with your booking, there are plenty of all-inclusive resorts further south, some so far south that the ride to the dive sites are mercifully brief. I've stayed at the Occidental Grand and Secrets Aura. Both were very nice resorts, but Secrets had better drinks and, for the most part, better food.
