The hotel is not right on the beach, and the beach is public, so they don't serve alcohol there. People do day-trip from Maui, and this is the closest beach to the ferry dock, so there will be people around.
That said, there are 2 pools, one of which is for adults only. Hopefully they police this well if there are kids being kids
If you're comfortable spending $1,000 a night for a hotel room, and then more for the overpriced food and drinks, then go for it.
I'm heading there next week!