Many many people play HSX (or attempt to) and some do not read the rules and have no idea about opening adjusts, starbond adjusts or how funds work. Those players simply buy their favorite movie stars and movies that they are interested in seeing. They also buy stocks based simply on news.
As you pointed out, yes, many of those types of players bought RMARA based simply on the news item. It happens.
But as DTravel also pointed out, her next adjust will be moving her in that direction and perhaps alot of players who know what they are doing became aware of her upcoming adjusts after researching her because of todays news.
The first kind of players above (who dont know what they are doing) are refered to as "sheep" by the experienced players. Sometimes in certain situations, you can make money by knowing when and which way the sheep are gonna herd (this is called "playing the players").