I work in enterprise software, trying to improve it one company at a time, and the biggest niche I see for excel is bypassing existing security mechanisms or procedures. We tend to expose data to users in a secure manner based on roles or authorities. But once users can export the data into excel, all of those security mechanisms are bypassed and they can send the data to other people or take it home.

I've even seen instances where excel exports are used as disaster recovery mechanisms.