Not sure I understand your 'because' here. Blockchain is helpful in making data public and persistent, and not under control on any one individual.

You might also be interested in geohashing as a more user friendly way to group nearby posts, although lat/lon is easier for a cpu.

Perhaps I'm not educated enough with blockchain to see how it can help with Habitat, but I'll investigate it, thanks. I'll also look into geohashing. I've never heard of it before, but I have been thinking about the issue of multiple posts for the same location and how to deal with that, so geohashing might certainly help with that. Thanks again.