Dates in Roadtrippers are currently built to reflect when you arrive, not necessarily the duration of time you’ll be at a place.
If you're staying in the same spot for multiple nights and want that to show on your trip, you can add that location to each day you’ll be there. This helps Roadtrippers correctly route your trip from that overnight stop each morning if you're using routed waypoints.
To add the same place to multiple dates, click the +Add Waypoint button at the top right of a date in your trip Itinerary. Then, type the name of the place exactly as it appears in your trip, and add it again. Once it’s added, you can drag and drop it to the correct spot in your itinerary for that day.
Alternately, you could rename your multi-day waypoint to include your length of stay so that is represented to you visually, but doesn't repeat each day. That would look something like this:
To do this, click or tap a waypoint and enter a custom name that includes the stay duration:
If having a better way to represent multi-date stops is important to you, please add your vote to our feature request for better Multi-Date Stop Representation!