All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
We do not see in what you mentioned anything that makes your action prohibited, unless there is a condition that you must buy before you become entitled to obtain the reduction points. Therefore, if this is a condition, and you enter just to see what they have (and not to buy), then you would be violating the condition, and you are thus not entitled to benefit from the points you obtained. This is because, in such a case, you would be obtaining the point by use of trickery.
Allah knows best.