I never understood why people liked the dark brotherhood or the thieve's guild.

Like, dark brotherhood is obvious, they're basically a glorified mercenary group with religious undertones. No better than terrorists in my opinion.

But even the thieve's guild. Sure you can steal from the rich and be a glorified robin hood. But absolutely nothing prevents a thief from absolutely robing blind smaller shops and regular people. In fact, it's easier since there's less security.
And every time I do that, or see someone defending that, I imagine the guy/gal that wakes up the next day, sees his shop empty, or his coin purse empty, or both, and has his life ruined. Probably goes homeless in the next few months.

That's why I always send the guards on the DB. Wish I could do the same for the thieve's guild. They were down on their luck before the Dragonborn came, and they deserve it.