So if I'm getting what's being said here correctly it's less "Grindr shared information" and more "Publicly accessible profiles were scraped." So....yeah, I'm kinda with Grindr here. If you make information public then don't be surprised when third parties get their hands on it.
On the other hand, given the nature of Grindr, if you're HIV positive, on Grindr, and trying to hide your HIV status....yeah, I've no polite words for someone who does that.