Some speakers do allow recording at no additional charge. Some do not wish to be recorded at all, and others agree to for an extra fee.
It is important to make your requests known in advance, prior to booking the speaker. Photography, filming or marketing should be discussed and agreed with the Speaker, so that all requests are included and agreed within the contract.
To remain transparent, my policy is that video/photography is accepted for internal non-commercial use, on the proviso I also get a copy of all footage prior to any editing. I very much support the use of video/photography for the promotion of the event, and happily provide a bespoke promotional video for clients shortly after booking has been confirmed.
However, having worked extremely hard to create content specifically for each audience, I take great pride in my work, as like yourselves have a business brand to protect. Therefore, I have an ongoing commercial relationship with a specialist Intellectual Property Law firm, with whom provides a legal framework around the content I deliver. I therefore, do not agreed to any unauthorised recording of my presentation or the commercial use of such footage however gained without prior consent.