Why does matter obtain electric charge ?

All matter is made up of atoms and/or molecules.

Although normally the materials are electrically neutral, they do contain charges; but their charges are exactly balanced.

Forces that hold the molecules together, forces that hold atoms together in a solid, the adhesive force of glue, forces associated with surface tension, all are basically electrical in nature, arising from the forces between charged particles.

Thus, the electric force is all pervasive.