Googling “tripadvisor sawdust floor” yields some results, including the Red Dog in Juneau Alaska and Saloon No. 10 in Deadwood South Dakota. Continuing down the page would probably produce dozens of them.
Maybe it is still an Alaska thing, I’ve seen it at Kenai Joe’s in Kenai, and the Salty Dawg in Homer.
The North Woods Inn in Covina, CA, has a long history of sawdust and peanut shells on the floor.
In the early 60s, in rural PA, it was not that unusual; at least common enough not to warrant comment until years later when the practice had begun to disappear. Like clouds of cigarette smoke and semi-illegal gambling devices (and kids being in such joints with their male relatives) it was just the way it was. I also remember them in some road-side eateries and other places too.
Some places were sawdust over wood flooring but some were basically just sawdust over dirt.