Even if everybody eats twice as many animals as they do now and moves further away from their workplaces, Earth will remain a more livable place than Titan. Maybe that isn't true if we kick off a nuclear war, but it probably still is.
Global warming? Titan's atmosphere is literally not breathable, and the outside temperature is colder than any place on Earth.
Food scarcity? Nothing grows on Titan. If you're growing it indoors you might as well grow it in your underground bunker on Earth.
The only way in which a colony on Titan could be less dangerous than Earth is from other humans trying to kill you -- the argument basically turns into "Let's escape the assholes trying to kill us." Even then, it'd be easier to make an Atlantis underwater (or any number of less far-fetched ideas) than to get to Titan.
Never mind how elitist and utopian and short-sighted the "get to Titan to escape stupid people" argument is...