Acrylic can actually be more expensive than glass, but offers many advantages. Acrylic is often clearer than glass (which can have a green tint).

Due to its lighter weight, acrylic is also more cost effective to ship. Acrylic is also flexible, making it less likely to break than glass.

Acrylic weighs less than half that of glass. It is much stronger than glass and thus more resistant to strokes (10-20 times). When it shatters, it forms large, blunt-edged pieces unlike glass. While scratch-resistant acrylic are not nearly as scratch-resistant as glass.

There are different kinds of acrylic which are more suitable for different applications.

Standard clear acrylic may look too plastic-like to pass as glass at the edges. But when it is used as a glazing material acrylic is very effective. 

Acrylic expensive than glass, but its strength, clarity, and lightweight properties make it a superior choice for many applications.