Why would you be upset if they're no factor for you? Are you one of those drivers on the highway who speeds up when you see someone about to pass you?
No, I'm not. I have no problem with people passing me on an expressway (or in cruise flight) but I would take exception to someone cutting in front of me when I'm in a queue for landing. It may not be illegal but it is impolite. Rather like entering on five mile final when aircraft are established in the pattern and forcing everyone else to extend or go around. Legal maybe, courteous, not.
This does not imply that anyone wins when he goes full speed ahead into the busy harbor.
Standard procedure in Miami. I grew up and learned to drive in New York and never witnessed that as common behavior until I lived in Miami. And it ain't just highways - it's everywhere. You put your turn signal on to merge into the next lane and that is the signal for the driver to close up any gap that was already there.