No, I have never dropped the trailer to go site seeing. If I unhitch, it's always at a campsite or home. Otherwise, it stays hitched. Call me paranoid, but I've got too much invested in time and money in my camper(s) for a criminal to vandalize it or steal it.
At most tourist attractions, you can find somewhere to park tow vehicle and trailer. It may mean walking a little distance to see the attraction, but there is almost always somewhere.
If you unhitch to drive around an area, your camper is much safer and better off at a campground, even if just for an overnight. With RVing, it's ALWAYS about safety first, always. How you drive on the road, the speed you travel, where you camp, who you associate with, where you shop, visit, and explore. Call me paranoid, but when traveling, you have to be if you want to return home with good memories instead of heart-break.
Find a campground and unhitch.
The only time I unhitched trailer from truck was once when we needed to run the truck through a self-car wash and wash the thing. Of course, the trailer would not fit inside the bay. We had to unhitch.
The other time was when our truck broke down and we were in the middle of no where. We got the truck towed to a repair shop and we stayed in a motel for 3 days. The trailer was parked outside our motel room. There were no campgrounds anywhere in that region and this was over a holiday week-end when everything was shut down. We had no alternative except the motel. No power to the trailer at all and we managed to keep the refrigerator cold and even kept the ice cream frozen. We were not set up for boom docking.
This is how they towed the trailer to the motel. We then unhitched the trailer, and the tow truck took the truck to a Chevy repair shop, some 30 miles farther down the road.
After 3 days in the motel and the holiday week-end was over, we hired another tow truck to tow the trailer to a near by campground that was near where the truck was being repaired. We were then able to get a car rental and we were at this campground for another 5 days while they fixed the truck.
It goes without saying, we never made our destination. And imagine our shock when we went to the Chevy dealership and saw this:
Those were the only two times, ever, we unhitched when not in a campground or home.