Kurotowa
Legend
I mean, that's true of any campaign hook, isn't it? At least with the Thieves' Guild concept you've got a lot of fertile ground for roles and backstory. The housebreaker, the enforcer, the informant, etc. And then you've got past jobs done together and friendships and rivalries and all that good workplace drama stuff.I find it the opposite. "You're all part of a Thieves' Guild" is right up there with "you all meet in a tavern" unless you put some solid work into the guild and its role in the world and its relationship to the PCs.
It's a great hook if everyone puts in a little work, which you can't say of "you all met yesterday in a tavern".