All switches have this problem, even low-voltage or AC ones. Slow switches, or switches that bounce, create arcs. This damages the contacts and can be hazardous.
This is one reason switches are "clicky". The action of completing or breaking the circuit must happen quickly. Switches have springs in them, which ensure the switch goes between the two extremes as quickly as possible. The springs oppose the motion for first part of the travel. Partway through the travel, they suddenly start to assist the motion and force the switch the rest of the way.