I've just about seen it all when it comes to playing this wonderful game. From the bar stool bangers who act like the course is a foot ball field and we're all there to fight onto the drunk pissing in the fairway and passing out at the next tee.
I played solo 3x this last weekend. I had to "prove" to a fivesome in front of me that I need to play through. Thankfully I didn't snap hook it, but blasted it 280 over the trees on the dog left further than anyone in the group. Old men foursome that took 15-20 min per hole, refused me to play through and scowled as I passed them onto the next hole. Listen to a regular yell from two holes over as I hit my approach and next hole tee. Had two approach shots from opposing hole hit into me with no warning. I purposely hit into a twosome that wouldn't let me pass played it off as I didn't know any better and hit my GIR to joke about "tour sauce" and had them laughing before I peeled out. Thankfully my Sunday game was just pure bliss and hardly any action on the course.
I've also been the ass that was upset and yelling as to why a foursome on a dog right that wouldn't let me pass only to blow by them seeing there was a group on the green. I'd say that moment humbled me and taught me not to be such a jerk. I now try to keep in mind we all payed the same to be there and not everyone is on my time table. Simply asking the group ahead if I can pass or play through face to face works most times.
Personally I've found that if you go to the group with a huge smile on your face and come at them with a relaxed attitude it usually eases the tension and you can easily talk it out. Most times in your favor.