In 2374, the ship's main deflector was modified by Seven of Nine to generate resonant graviton beams to open a quantum singularity into fluidic space. (VOY: "Scorpion, Part II")
I mean, it makes sense for the purposes of the lore. The deflector is the largest power using device on the ship that isn't the shields, and it can direct that energy outward. It can't solve every problem, but any problem that can be solved with "we need a lot of energy shot at this thing" then the deflector dish is what you use.
I don't remember which episode it was, but they basically state this about the deflector in one of them... TNG or Voyager, specifically.
Ensign Beckett Mariner used radiation from the main deflector in combination with parizene gas to reverse the partial transformation of the USS Cerritos by terraforming emulsion in 2380. (LD: "Moist Vessel")