Use of trademarks and images question

No matter how specific you make the question, the answer is always going to be the same: trademarks exist to protect a company's brand, logo, etc., and images and written materials are similarly protected by copyright unless they are in the public domain. The only ways you can be sure that you can use someone else's content is a) if it is stated somewhere on their website that the content can be copied freely, and b) if you ask them if you can use their content and they say yes. The fact that other websites appear to be using logos, etc., without permission doesn't mean that it is okay to do so.

There is no need to be put off your idea of creating a fan site by any of this. Just be careful that any content you publish is not in violation of anyone's rights as far as use of trademarks and copyrighted content goes. It's possible that some companies or celebrities might have press packs containing images or similar content that can be used with no problems. The only way to find out is to ask them. Better to do that and avoid any problems.

Well you are talking about two different things comparing the Olympics to gaming.

Many gaming companies are very laid back in their approach to trademarks because there is such a huge number of fans and fan sites that do more to promote the game than harm it. They would protect them if you started using them in ways that would infringe in a more harmful way, such as making and selling merchandise with their trademarks as opposed to a blog or YouTube channel.

You will always find examples of willful trademark abuse. Some is out of ignorance and others because they just manage to get away with it. How it is enforced is up to the trademark owner. Some are very litigious. Others are less so.

Ultimately you need to evaluate using your own risk tolerance and conscience on a case by case basis.