There are elephants in the room: 1) lack of women in the industry <--- means an increasingly out of whack male:female ratio in the city which has many problematic pile-on effects.
2) simple feelings of being left out...that's what people don't like about Google shuttles. They're mysterious. Let people in them, see what they are, see how they're really not that amazing or great: but then that would hurt recruiting.
3) Arrogance of many tech workers: anti-social intercommunication skills etc. We all know this is undeniably true. Sure we may be nicer than most finance types. But are we more out-going? Do we try to connect with our community on an emotional level? Certainly not more than most, and I'd argue a heck of a lot less than most.