Bae'zel
Hero
I think that this really depends on the context at hand. Is the 1st level rogue a 16-year old newbie who lived their entire life in one alley? Probably not. Is your 1st level rogue a 50 year old commoner with a life of experiences, forced to take on a life of crime late in life? Perhaps!no, the idea that your 1st level Rogue is one of them is
I always assumed that these sorts of declarations are not automatic; that there should be some back and forth between player and DM.
Personally, I love it when players suggest these connections and contacts. Saves me some work improvising. However, I always have follow-up questions: "how did yo make this contact? what was the nature of it? Why havent you mentioned it before? Is it because something went badly last time you interacted?" etc. To keep things interesting.