It isn't Synergy alone, its the fact that new ammo uses absurdly difficult items.

Antlion Jaw are rare drops off Antlions.
Oberon Bullets require a Campaign drop.
Fusion Bolts use ore mined solely in a CoP zone.
Dark Adaman requires Darksteel and Adaman ores.
Dweomer Bullets require a Campaign drop.

Unless you go out of your way to farm these, GL ever being able to find a stack for a reasonable price. Theres nothing wrong with paying for ammo but when a single stack is ~30k-80k, its ridiculous.