Do I Have To Waterproof My Concrete Steps

[Missy H.]

The front steps of my house is starting to crumble. The tenants used snow salt this past winter which cause the concrete to begin to deteriorate at the edges. I called a concrete/mason company an he said that partof the repair would involve waterproofing the steps and this would be an additional $150 to do.  

My question is, I understand why one would waterproof concrete for a basement, but why would someone have to water proof concrete steps?  

Thanks