We use this at work and don't have any of the issues you are talking about. The only time I've seen the karma bot used is when an individual goes above and beyond for another individual. I have yet to see any other use of it, such as what you described. We are a remote-ish team (we have people in a centralized office but also have workers throughout the country) and all of our communications go through Slack. The use of karma bot for our department is to recognize hard work to all, even those who aren't in the office.