The hit CG-animated movie opened to a strong $33m box office this weekend, but claims emerged that costs were kept low by firing people who refused to work without pay and that many animators were omitted from the film's credits in retaliation for leaving.

The production cost were kept low because Greg would demand people work overtime for free. If you wouldn't work late for free your work would be assigned to someone who would stay late or come in on the weekend. Some artist were even threatened with termination for not staying late to hit a deadline.

The animation department signed a petition for better treatment and paid overtime. When the letter got to Annapurna they stepped in and saw that artist were payed and fed when overtime was needed.

Over 30 animators left during the coarse of the production due to the stress and expectations. Most of them left before the paid overtime was implemented. This was met with animosity and was taken as a personal insult to the owners. Their names were omitted from the final credits despite working for over a year on this film.