I would imagine most of us would. The smell would get out of hand otherwise. If its sucking in 70% or more Humidity levels then a dehumidifier is a great tool. I just have mine on Auto at all times and it cuts in and out if it needs to (mainly in winter and/or rainy days)
I would assume that those living in dry areas would not need one. We had 35C the other day and the humidity levels were over 90%. Tent would of been sucking that humidity in and plants transpiring would of risen that level.