[Mod Hat]Let's keep the sarcasm down, please. [/Mod Hat]
Southwest FA's are known to comp drinks (either openly or by failing to collect a drink coupon) for all kinds of minor reasons. I'm not surprised that being a member of the Southwest "family" is a good enough reason for some FA's. I very much doubt this is an official policy.
And yes, the FA's authority to comp drinks without accountability is subject to abuse, but it seems to work reasonably well.