On StubHub you can either go to the filter option on the event page and click on the checkbox that says Show prices with estimated fees or I believe that is not checked by default so the prices you see on the main page will not include the service fees. Those are added after you cart the tickets. StubHub has various fees that cannot be explained honestly and they vary widely throughout the site. My best advice is to be careful to check the overall cost and if you're not comfortable with it, look for other tickets.
Hey there, @abigailmcclain, ticketmvp is correct about the filter option! Also, it looks like we are helping you on Twitter and we can continue to help you there. if that doesn't answer your question.