Why is this workshop so important?

I just started playing Die2Nite and my group seems to think a workshop is very important. Why is that?

A workshop allows you to convert common, otherwise useless materials such as rotten logs and scrap metal into more rare materials that can be used towards building up construction sites, such as twisted planks and wrought iron. Without a workshop, you'll struggle to find these materials and you'll be unable to make the defenses your town needs to survive for a decent amount of time. The workshop can also be upgraded with some defenses of its own, such as the Screaming Saws, which offer 40 extra defense for your town. Finally, the workshop can be used to open those closed cans without a can opener, allowing for more food rations to be obtained easily.

Particularly because of the fact that it makes it easier to build everything else in the game, the workshop should always be built first. It is your number one priority in a new town(along with a tent for defense).