In this case, given that we don't know anything about the specific context or circumstances of each party, if there was room to move where it would have been possible to see around the person standing, then that would have been the easiest solution and would have avoided any confrontation. Directly confronting another guest can be iffy. (There is a big difference between "told" the other guest to sit and "asked" the guest to sit.) Usually it is much better to find a nearby CM and ask him/her to settle the matter. When we've viewed fireworks from that area, there has been a mix of people sitting and standing. It just depends on where people are located. And, as far as I know, there is no firm protocol for sitting or standing in that area, unless CMs tell you to sit or stand. Some areas are better situated for sitting, e.g. steps or planter walls. Other areas are better for standing. Then there is the VIP section with chairs (I don't know if this is always there). Usually that area isn't packed, so quickly finding another spot should not be too difficult. When a confrontation needs to happen, we usually find a CM to do the job. If they can see a solution that can avoid any confrontation, they will suggest it and usually take care of it.
