Wow, I didn't know such a concept -- or a website -- existed. I'm interested.
Actually, 3-4 years ago we took a wonderful driving vacation among the Western National Parks, and one of the best moments of that vacation was a tour we took at one of the lesser-known state parks. Our guide was an older man -- probably in his 70s -- and we thoroughly enjoyed his company. As we drove from spot to spot, he told us that he lives in Texas but spends his summers in Wyoming giving tours. He was a good speaker and very knowledgeable, and both of us said afterward that we could see ourselves doing seasonal work of that type after we retire.
Looking at one of the websites, for example, I saw that an Alaskan campground is hiring people to work as campsite hosts. It pays a stipend plus a free campsite. As long as it's not mid-winter, I'd jump at the chance to do that! I've never been to Alaska.
I would not want to work my fingers to the bone in an Amazon warehouse, and I would not want to NEED the employment, but I would be very willing to work a while in this place or that so that we could purchase a luxury or two without dipping into the savings account.