Kids, safety, convenience, positive encouragement, all these things help. Not everyone is as privileged as you where you can easily just go outside and leave your home without a care in the world.
In what world are you unable to do the above, but perfectly able to have this solved via electronic workout devices.
Do they need an electronic workout device? Nah, but if you're legitimately helping someone to achieve motivation or be safer in taking care of themselves, then the product has value.