I appreciate the comments that said if arriattu had complained directly to Karwa, then he should have waited for their response, and maybe, on the surface, that seems reasonable.

However, in support of arriattu's actions in posting the information he did, I'd point out that had he waited, Karwa may have taken some time to respond to the complaint, or they may not have responded at all.

In the meantime, had arriattu done nothing while waiting a response that might not have been forthcoming, people would have been unaware that this was happening.

I think it's a valuable public service to highlight where problems are occurring so that people can hope to avoid encountering the same problem or be prepared in advance and think of how they might deal with the situation if they encounter the same problem. I think people should do this in addition to making a formal complaint.

Also, I'd suggest that this kind of information is useful in another regard: If lots of individuals encounter this kind of problem, maybe a couple might make a formal complaint, whereas others might just pay up the extra (and be ripped off in the process) or others might refuse to pay, but do nothing about it.

If the information is out there, in public, if it happens again, the people who might have paid and been ripped off, or people who might have paid but didn't complain, officially or informally on a public forum, they would know if it's a practice that's becoming widespread, and they can be encouraged to make a formal complaint to bring it to a halt.

For those reasons, I think arriattu is in the right in this situation, and kikomondos has overreacted badly.