The way stock is managed in this situation is desirable for many in that case otherwise shopping on a site and adding to cart would not be viable or use friendly.
What you mention about not closing a browser though is a case that is not true. IF you go into the shop settings in the admin you can see the cart restore timer which is by default 24 hours but you can change this to as low as 1 hour if you wish.
This is the response I got.
I will look into this.
I tested filling the shopping cart then closing the website. The only way I could get the shopping cart to empty was to close the browser. Are you saying it is different to this?
You waited 24 hours or changed the cart settings?
Who is Kim?