The Maquis didn't just target the Cardassian Military.
Their chief target was the opposing Cardassian farms competing for resources on the same planets.
Civilians vs civilians.
Problem is that it became a conflict orchestrated by third parties (3rd and 4th?) quite quickly, that the Cardassian Military were arming and bankrolling the Cardassian farmers under the table just like the Maquis were being funded and sourced by Starfleet howsoever discreetly.