There's a strong social benefit too. Being able to more comfortably spend time with friends and family you care about, even if they can't be vaccinated yet, seems worthwhile in itself. There's also the related consideration for dating, etc.
Unfortunately not. Being vaccinated doesn't stop you from having and transmitting the virus, only from getting sick. It won't be safe for you to see your friends until they have it too.
> He said the findings reflect an impact on blocking transmission and are very encouraging, hinting at mucosal immunity. "The data aren't conclusive but support this key benefit," he said.
Of course, if in the end vaccines don't prevent transmission, then they don't prevent transmission. But we don't know that they don't do that.