A recent psychology book covers the science of talking to strangers: "Once Upon a Stranger: The science of how 'small' talk can lead to a Big Life" by Dr. Gillian Sandstrom. Generally there seems to be quite a growing interest in researching both talking to strangers, weak ties, etc.
The book tells stories about her experience as an introvert and her journey in coming to love the interactions, using humility, humour, and science (both hers and that by other researchers).
A few points I like made by Dr. Sandstrom:
- low stakes way to create a sense of community, as well as addressing social anxiety that is more pervasive these days
- the existence of a "liking gap", where people like you more than you think
- there is value in these "weak" interactions, even if they're small
- most conversations don't go anywhere, and that's okay. Few are outright failures
- acronyms like QuICK (Question, In Common, Kindness) to think of conversation starters
- [EDIT: added] it can be easier to talk to strangers about some topics, rather than to close connections
- [EDIT: added after reading some other comments] it doesn't need to be about gaining "influence", "networking", etc.
[Note: I know the author, but it doesn't change the fact it's a good and useful (IMHO) book :)]