Do tax exemptions in America for certain organizations benefit society?

Sometimes, but like most things in the US tax laws are often abused and misused. A simpler tax system would benefit everyone more (with the exception of tax accountants, of course), but that’s not likely to happen.

Also why doesn't this disqualify religious organizations from tax exempt status under 501c3?

"no substantial part of the activities of which is carrying on propaganda, or otherwise attempting, to influence legislation"

at small scale, i would argue that they are more than inclined to help with society, local society at least. Small churches running a food kitchen on the weekend for instance.

It would be a pretty good incentive for private land owners to open up a community space on their property. Which would also positively impact the community (something i would like to do eventually)

Permanently Deleted

No, they do not. Tax exempt organizations shouldn't be private and also exempt from government oversight. I do think that legitimate small businesses should be tax exempt to simplify beaucracy, though.