The sponsorship itself is not an ad, nor is the stadium. But signs posted at the stadiums indicating the sponsorship could be considered ads. Likewise in the ca

The sponsorship itself is not an ad, nor is the stadium. But signs posted at the stadiums indicating the sponsorship could be considered ads. Likewise in the case of the website, the text indicating that the site is sponsored, which will take the user to the sponsor's site when clicked, is an ad. Thus, it is not unreasonable that an ad blocker would block it, even if it isn't "intrusive" advertising.