Reraising pocket AA, KK, QQ, theory question????

[HoldenFoldem]

I really don't understand why we do this. At 50 and 100nl where i play most of the time, reraising will often fold the original raiser leaving you with a small return for your big hand.

Flat calling disguises your hand completely and you can often win a huge pot by doing this.

I am aware of other factors involved but would rather hear from you all first, in this discussion, so i will better understand the principles involved in playing these hands this way.