Suppose to have an e-shop web site, how to take trace of the user wallet througth pages? The response should be to use Sessions, but how we know, they are based on the cookie capacity of the web browser.. What happen if the user have the cookies disabled?
The reply should be to use the GET method for pass parameters, but as we know, it's unsafe because external people could try an retry until discover it!

So my question is: great e-commerce site, such amazon.com, what method use for this drawbacks?