Because they know they have nothing left to offer the world. Since the poetic language of Tiqqun and TCI is just vague enough to offer Marxists the ability to impose a certain level of political economy over the texts, Marxists can try to claim them as Marxist texts even though they are not.
If it ever did, by now Marxism no longer has anything to offer revolutionary theory and practice; in their desperation to remain relevant, they grasp at anything they think might help them.
