Ok if you will answer on one question. you will win. If not - lose.
If bombarders's skill and they not imbalanced,
WHY 99% DWARF play with bombarders and not use snipers?
Answer me, genius.
This question has already been answered for the most part but I'll reiterate and add my own opinion.
The three biggest reasons why a lot of dwarf pick bombadiers is,
1- A lower gold cap cost, which I think is the biggest overall reason as people LOVE to cap block themselves and fit in every gold they can when using governor/army cap tile/advisor spot.
2- The more bombadiers you have the more beneficial blast off becomes, and this once again comes back to reason 1, with the gold cap so low for such a large portion of the game every player needs to really evaluate the best bang for their buck. In the early game, which I'm assuming is where you are, it makes the most sense to run bombadiers, exclusively even in some cases, a lot like lich and their gold spiders.
3- They are great for siege. The extra damage bonus against walls makes them ideal.
With all this being said they are still not the overpowered monster you are trying to make them out to be. Even with a max Grimms ammo capacity+trinket and the ammo reduction research they still run out of ammo for the majority of time when pillaging and against any good opponents. Once dwarf units reach level 10ish and academy 9+ they will want a healthy mix of deadeyes with their bombadiers or any and all high hit point units like calvary, scorpions, monks, foot etc will outlast the dwarf ammo and proceed to win an easy fight.
Any dwarf above level 30 who runs nothing but bombers will have a tough time against everyone except maybe a human player who only uses 24 pack units, has a weak Vega, no priestesses and no foot/virion. Lich will walk right over them, humans with calvary/priestess/archers will dump on them and a dwarf with the right unit comp will take an even bigger dump.