I am just wondering here.. Aren\'t the PayPal buttons that are dynamically created, very unsecure, and easily \"hackable\"?
Like so:
You are correct. can be easily manipulated on the client side. In the example you gave, this might be a form where the client is actually supposed to be able to set the amount, eg. a PayPal donate button. Otherwise there would need to be server side checks after this form submission to ensure that there is no funny business going on.