[Tcoat]

My car gets this every single time it is cold. My mats are saturated since I drive it at least twice a day when it is snowy. I get at least two coffees which pump moisture into the air every single day. The snow brush is usually still covered in snow when I put it in.
None of this is going to harm anything in any way and it will all dry up as soon as the weather is nice enough to drive with the windows open. People in humid places have a much larger exposure to moisture every day but since it doesn't make a pretty pattern they just can't see it. The inside of the car is manufactured using plastic, metal and fabrics made to withstand such things. It is not made of sugar that will spontaneously disintegrate because of exposure too a little moisture.