Imagine a classic prison escape scene. Maybe the one at the start of Out of Sight with George Clooney and Jennifer Lopez. You know, a cleared area, fences, guard towers, the works. Somewhere there's a hole with people crawling out.
The GM calls for initiative, but the guards don't see anything. All they can do is sound the alarm, and Seek (using searchlights). Then it's the inmates turn. All they do is try to avoid an encounter. The rounds pass by and not a single attack roll is made.
See? It's not that PF2 is exactly weird, strange or bad. Just... different.
I guess ... I'm not sure what you've been playing all these years CapnZapp. It's really so strange to you to start an encounter scene where one group is unaware of another? All your combats are just about people charging and attacking first round?
To me that sounds more like the odd viewpoint. I mean, I've played and run countless 3.5 and 4E games and this happens all the time. In fact THIS EXACT SCENARIO YOU DESCRIBE has happened many times. Are you seriously telling us that PF23 has introduced you to a new concept by having encounters that do not start with an attack?
Completely regardless of system, this would be a normal sequence in any game I run:
Player: I sneak across the yard, taking cover in the trees
GM: Ok, Let's go to initiative <People roll>.The Guards go first, but they don't see anything. Your turn
Player: I sneak across <moves figure>, getting a <X> result
GM: They don't notice you. Their turn, they have no reason to do anything ...
As a GM I'd usually run this not as an encounter, but there are plenty of reasons I might want to (and often do) ; there might be a trap or terrain feature that the players blunder into, or a guard they haven't seen taking a piss behind a bush they head to; or I expect someone to fail their stealth check and so expect a fun starting position on the tactical map.
Am I missing something? I honestly find it hard to believe this is something nw to you in PF2. But if so, congratulations! Pathfinder 2 has helped you improve your game!