No such thing as too much cream. This is what allows eggnog to absorb insane amounts of bourbon so you can look seasonally festive while getting sloshed. If you're too full before the alcohol takes effect, you haven't added enough.. Hmmm... dipping a Royal Dansk cookie in bourbon-saturated eggnog could be quite the holiday treat. What other foods are you looking forward to?
And eggnog is the perfect way to consume the bottles of cheap bourbon (rum, etc.) that you wouldn't dare drink straight lest you dissolve your taste buds and stomach lining that were gifts from well-meaning friends and relatives who have no taste in liquor whatsoever. Or at least serve it to your guests.