Think of the bounce on a wedge, or any iron, as an insurance policy against digging the leading edge of the golf club into the ground.
It is very important for any golfer to not only understand what the bounce is, but how to use it to their advantage. An excellent exercise to do every now and then is to hit a few pitch shots off of a lie board. This is a flat plexiglass board that most club fitters use in determining the correct lie angle a golfers irons should be set at. If you do not have access to a lie board, use a piece of plywood painted black. Just be sure to not hit any shots where the ball is too close to the edge of the board.
If the markings on the sole of the club are as pictured above you are using the club correctly. Should they be closer to the leading edge you might be in danger of sticking the club into the ground on your next chip of pitch. The most important aspect of using the bounce correctly is addressing the ball correctly. Take a look:
In the above image you will see the ball positioned in the center (watch out for too far back as it reduces the bounce at impact and makes it easier to do some gardening); the feet are fairly close together; and the hands and weight are just slightly in front of the ball, with emphasis on slightly.
As you go through the motion of striking that chip or pitch try to feel that the handle and the clubhead get back to impact at the same time - in other words don't allow the handle to get too far in front of the clubhead at impact as you are then exposing more of that sharp leading edge to the ground. And we all know what that can lead to.....