Request param is string but model still return data

[simpsons310]

Laravel version: 9.9.0
PHP version: 8.1.6

I have 1 route like this:

Route::patch('room/{roomId}', [RoomController::class, 'update']);

In the RoomController:

$room = Room::where('id', $roomId)->first();

In my database, in rooms table, I have a record has id = 74

When I try to call a patch to route room/74, in the controller, $room returns a correct Room model object with id = 74. But when I type some string after 74, it still returns the Room object with id = 74 to $room variable. e.g. room/74wasdsaw.
I also tried to dd($request->all()) and it returned 74wasdsaw

I wonder if this is a bug or a laravel's feature. If it's a feature, what is the purpose to?