I can't imagine a goblin being allowed in Baldur's Gate, if they're not being killed on sight by everyone and their grandmother.
I think there's a strong argument to be made that a place like Baldur's Gate would be more willing to let in a goblin or hobgoblin than someplace like Candlekeep. And even then, part of the fun of playing the monster races is working around issues like this, creatively. Disguise Self, Charm person. Massively high Charisma and persuasion, etc. Simply letting one of your other party members go in instead. I don't think it's impossible.
