Logical Mechanisms

I think I may have mentioned this about shopping in Ireland, but it's the same way in Germany, and it makes so much sense! I totally can't figure out why we don't adopt similar mechanisms in the US...

I'm referring to the shopping cart ("trolly") system in Europe. They are stacked together with a chain attaching them to each other. You insert one euro and are able to detach one trolly. When you are finished using it, you attach it back and your euro is returned. Simple as pie. This prevents trollies from being scattered all about the parking lot ("car park"), knocking into cars in the wind, blocking spaces available for cars, etc. Also prevents having to pay an employee to stand around outside in the rain/cold/heat, collecting the stray trollies all day long.

This is logical. Let's do it in the States!

I saw another incredible mechanism I saw was in a bookstore in Aachen. It was absolutely cold outside, literally below freezing, and the main front doors of the bookstore were wide open! What?? Isn't this a terrible feat, trying to heat the bookstore, while allowing the cold to gush in and/or the heat to escape?

The solution they were using is a wall of warm air! There was warm air being shot down from some mechanism lining the top of the doorway, creating a "wall" of warm air--you felt like you were walking through a thick layer of cotton or something, but it was the warm air pressing. Evidently this does a superb job of preventing the exchange of air temperature inside and out. Awesome!