Because you may be measuring different kinds and different volumes of materials. A 100 ml graduated cylinder would be useful for measuring water to make up a solution. However, if you were supposed to add 50 microliters of another material to the water, that cylinder would be useless for measuring such a small amount. You would need a special pipette. If you were working with solid material like soil, neither the cylinder nor the pipette would be very useful. A wider container like a beaker would be better. The type of glass used is dependent on the final use ie. oven, microwave, freezer, etc. Other uses might be for table wares, lighting, decorative pieces or electrical insulators.