When i use my go pro it is on constantly for 2 reasons, the batterys life time last longer as aposed to it being on and off, and when you turn it off is always when something worth videoing happens.
things like youtube are also a great way of storing video’s that you dont really car if some one rips off instead of filling your hard drive, it also means when your round at your mates you can watch it without taking your desk top with you.
If you don’t like them don’t watch them.
Its like me saying why does everyone (not litraly) ride £4000 full sus bikes, im by no means fit or good, but I over took plenty of people on the latest bikes on my 10 year old inbred today. does it affect me NO.