Can't think of one? If you can, how new or relevant is it?
A lot of companies can't afford billboard space. What they can afford is social media marketing. The only thing you need to market anything online is, well, the internet. A monthly subscription to your local internet provider is a lot more cost friendly than a one time fee for a billboard. Sure, you can pay for online ads but getting your content out there isn't that difficult.
Have you ever looked something up online and the noticed ads for it almost immediately on all of the apps that you use? That's called retargeting. Companies pay to set up ad campaigns and then use the data you've looked up to keep their brand top of mind when you head to other apps and platforms.
When you head to a site and get that pop up that asks you to click accept or decline? That's usually asking you about content sharing and cookies. That's how they're able to use the cookies to retarget their brand to you across multiple platforms.
Not all companies use retargeting as a marketing strategy. Some simply use their online presence. They actively share their content, their employees are engaged, and they know who their target audience is. Consistency is key. If your company is posting but your employees aren't actively helping to push the content via their own platforms - you're basically throwing a baseball into an empty field [there's no one there to catch the ball].
Regardless of whether there's a paid strategy in place, social media presence it key for companies to keep their brands top of mind for buyers today.
Oh, and billboards don't have cookies.