Tilting you windows is a nice option that i rarely use. Most if the time its STOẞLÜFTEN as we germans like to say (opening the windows wide up to really let in all the fresh air).
Is that not something that Americans do too? As far as I know the need for STOSSLÜFTEN is because we're building our buildings so air tight, that there is little circulation.
Yeah, being able to open the window just slightly from a different angle doesn't seem like that useful of a feature. Also in the US we mostly have a different style of window (see below).
It's rare that I want to open a window, but only slightly open it. Normally it's all the way open and I probably put box fan in the window to pull air through.
You're correct that many houses these days are built too air tight, but for older houses that were built before AC the house was often designed so that you could open windows on different sides of the house to create a cross breeze. So for example, you could open up windows on the East and West side in the morning and the temperature difference should create a convection breeze through the house.
It is only useful if you have a bunch of stuff sitting in front of you window and you are able to tilt another window on the other side of the house but its really not that big of a deal.