Leopard gecko is eating the moss in his tank?

If the gecko is purposely eating the moss then YES remove it as soon as possible!!! if the gecko eats too much, it will Develop an impaction. An impaction is basically when a gecko eats something its not supposed to, and it blocks its stomach, which defiantly leads to death!! try something such a regular paper towels in the hide, NOT shredded, just dampened. i hope this helped!! any more leopard gecko questions just email me!!! :)