Can wearing shoes that are too tight cause hammertoes?

That is true. Wearing shoes that are narrow and toe tight around the toe can cause the toes to become bunched up. Eventually the toes might be put out of alignment and expose you to the risk of developing hammer toes. High heels and unsupportive shoes can further predispose you to developing hammer toes. Ensuring that you have shoes with a wide unrestrictive toe box and adequate support is the best choice in shoes for you to avoid developing this condition.