At every companies I've worked at the CFO always has a large presence at every townhall, after all they are the one who is responsible for sending your paychecks on time. As for CTO, yeah it's a mixed bag in my experience, I mostly see them as just another layer between the CEO/COO and the principle engineers. Maybe that's exactly what they want though.
The CTO role is to be invisible to the business, and do that by ensuring that the tech org is working