No, not possible to hide Master page or objects on Master page. The min occurrence on Master page is at least 1, can not set to 0. For the very first Master page it has to appear at least one time. If it is subsequent Master page appearance is dynamic and do not need to show up at all.
Silvia - I selected the form (that was on the second page) and click on Palettes - object - select subform tab. changed content dropdown menu from Flowed to Positioned and click on check box (allow page breaks within content).
that actually get rid of blank master page showing up as actual form.