Webinars: where is the possible charges info?!

Hi, I just assisted the AWSome Day last month and now I'm being charged for instances that I left running after following the very steps the instructor presented. My point is: there were no warning words regarding possible later charges in the case you follow the instructions and it hit me by surprise. Have anyone found the same issue? Or am I wrong and there is actually a document prior to or during the webinar covering possible charges issues? I think at least in this case the webinar should also reinforce the knowledge of having RDS-related charges in case you do what they are showing.