Again....fastest way to reduce the zerg hunts has become:

1.- Lower the myth/sold rewards. Getting enough seals for an oil/sand is useless if you dont have Sold for said item. This will make ppl also do dungeons/roulettes/raids/frontlines.
2.- Since you can pretty much get unlimited oils/sands with hunts, remove them from the weekly lookout in ST/Coil. This will send ppl who enjoy raiding back to raids.
3.- Make frontline reward allied seals. This will send everyone who enjoys pvp back to frontlines.
4.- Increase the reward for dailies. Make them give something around 50 seals each day. 10 days to get an oil if you want to avoid the drama and do the daily only.

You want lots of ppl doing lots of different stuff. Not all the server doing just one.
If not, the other option would be putting a 750 weekly cap = 1 sand per week.