About the only time I get upset with people is if they break normal traffic rules out of pure ignorance. That causes accidents and can get people hurt or killed.I often think of how well traffic would move if everyone was just 5% more considerate towards each other. (This includes merging onto the freeway also.)
Today I pulled up to an intersection that had stop signs going one direction (on both sides), with the other direction having the right of way (state highway). I pulled up to the stop sign, intending to make a right hand turn. There was a small pickup on the other side also stuck at a stop sign, attempting to turn left (same direction as I). We were both yielding to traffic for a good 30 seconds, he was there first.
When traffic cleared, I proceeded to make the right hand turn as I had the right of way. He/she ignorantly turned same time as I did. So I hugged the shoulder (so he wouldn't hit me), stomped on it to get ahead and waved the one finger salute. Sorry, not sorry. If they keep driving that way and don't learn from mistakes, they're going to hurt someone eventually.
Same goes for merging. By the time you're nearing the end of the on-ramp you should be going near or at the highway speed unless something prevents you from merging (stuck traffic, both lanes used, etc.) It never ceases to amaze me how many people I get stuck behind going 35-40 at the end of the onramp and either jut ahead of vehicles causing them to brake, or they stop at the end of the onramp when they could have merged gracefully if they were at speed.