Something creepy about a coffee shop re-tweeting a Swarm checkin 3 hours (or more) after the fact. If you want to leverage social media, why not engage with the person when they check in? It’s not like it’s difficult to set notifications for mentions on just about any device, so you can’t use the excuse you can’t be monitoring 24/7.
Wouldn’t the impact probably be higher? If they are publicly sharing where they are, and you reach out and say hi, maybe buy their cofee or give them a scone, the chances they share that interaction on social media would be far stronger than an hours old retweet.
And if this sounds like someting you need help with, buy me a coffee and I’ll give you some more suggestions.