I'm not going to tip for the first time in a while
Why would you refuse to tip?
I'm pissed off with the whole service and I want to leave a message, its time for a change.
If you think that a service wasn't good enough to deserve a tip then you shouldn't leave one. On that same hand if you think the service was that bad you should look into filing a complaint with the management so that they can get that issue resolved.
Nah, I will just not tip. It's not logical to do so.
Tipping is technically a suggestion. Others might think you are rude if you don't tip though.