You can build a warband to have enough morale bomb that far exceeds the max health of the average player. Without breathing that hard I can make a warband with 28,800 instant damage 30ft morale bomb. All I need is the organization/coordination to pull it off. That's 4 shots of a gun I can bring to deal with the zerg. That's Theoretically 36 dead player's. I can build much larger instant damage morale bombs then 28,800 30 ft if I wanted too also. But it comes at a cost depending on class make-ups. AE instant morale damage is literally how organized play can counter number's larger then themselves. Raze bomb's is kitten's play compared to what this game was capable of doing.
The zerg will only shoot me once with their morale bomb because that's all they can do because they lack the organization/coordination/discipline to due anything else. Zerg play can't control say "only bomb with group 1, group 2,3,4 hold bomb for 2nd wave of their push." Zerg play doesn't have the organization/coordination and discipline to deliver several shots of morale bombs. If I lose say 6 player's to a morale bomb I still have 21,600 30ft morale bomb left. I still have 3 shots of a gun which can turn the tide. Which is still theoretically 27 dead player's. I personally don't even have the organization/coordination to pull off the above but I am actively working towards it.
Each death of a morale bomb component decreases the morale bomb coming at you and stagger's the overall strength. The morale level of everyone on your team is super important and ST death's stagger's that. Which is why ST has some importance in organized vs organized.