They sometimes rub me the wrong way too, like when I say something in Facebook messenger and I think it warrants more of a reply than just a thumbs up. This used to just happen with one particular person though, and we are not very close anymore so we don't message back and forth anymore.

On the flip side, I've used the thumbs up before, like when I've been very busy and didn't have time to have an actual conversation. Its like saying 'ok." Or "I hear you, over and out."