Yes most sites are set up that way, but they are also set up to let the user pick it in a control panel of some sort or lets them know it will change their defaults. Not like PP when you change a view it makes it your default without telling you.
It is not that I don't want users to change their view. I want it not to be saved to their cookeis. I have one of my PP galleries set as I said 1 row and 4 images for a reason and if the users wants to view it just one time at 12 per page then it should be just that. One time until he leaves that gallery or logs off then it should go back to default.
I think if the user wants to do a one time view of 12 images per page then he should be able to do that and not have it set his cookies to that default without it telling him it is going to do that. Having a persons cookies set without telling them is not right in my opinion. Your opinion may be different on this too. But when a program is doing something to my cookies without me knowing it then I am not happy about it.
If it is going to be set in cookies by what the user last viewed them as then I think that it should be an option in the admin area to allow that user to pick there default or not.