That behavior isn't discouraged or punished. You and your discussion counter-party can send each other sats and it has no effect on your trust. If the discussion is in fact niche and no one else appreciates it, you won't get paid rewards, but that's about it.

k00b

I tend to upvote comments and content that isn't widely noticed or understood. I don't think this behavior should be discouraged with demerits otherwise it encourages cliqueiness and dog piling and discouragages discussions between individuals that are "paying" each other for their helpfulness.

Brunswick

SN release: enhanced trust algo and more tangible rewards 

The downside is the posting/comment cost (admittedly low atm), and if you upvote poorly, your trust reduces as does your influence and upvote rewards.