This is very interesting. If this is a regular company, I guess your assumption is correct that no one would exercise those warrants since you can buy shares cheaper in the open market.
However, with a resource company like ARU, it is a different story. If the insiders believe that a buyout in coming and that buyout price will exceed the $9.375 per share warrant price ($37.50/4). Then why not exercise them regardless? May be we should watch and see if they are exercise to give us some indication of how strong the conviction is with these people.
Yes, all options and warrants were assumed to be exercised when you calculate the fully diluted earnings per share.