Similarly if they are reading about some music gig coming up in the area they need an ad or offer for 25% off burgers at hipster burger joint du-jour that covers that night.
I once worked on a hyperlocal project that was funded by a television company to actually curate a stream of interesting and novel content about the local area. These were trained journalists curating sourced and self-created content. If the content was good enough then there would be ad-revenue (and deal placement) to follow, or so you would think. Turns out nobody was interested at all.
I don't think user submitted content will be engaging enough, but we'll see. I think anyone with a disposable income that could be targeted for hyperlocal ads or deals doesn't have enough time to use this app as well as twitter/facebook/whatever.