The platinum tickets are not directly in front of the stage. They are the front row of seats which is several meters behind the standing General Admission. I suppose these are for people who would like to sit, have lots of money, but also want to be towards the front, which seems to me would be a smaller market. A better indicator is whether GA and the majority of the other seats are sold.
This is a very decent thing to have done. Some have systematically claimed the show sold out weeks ago when it hadn't. What you have done is provide access to tickets for those that may want them. Decent.