It's a big deal in my opinion.
I was someone who used to SH, (although I always used to hate that term and never thought it applied to me), and had the same argument that other ways of venting feelings don't feel the same, although now having fought those urges, having a few more years of life behind me and having kids I can see it from a different perspective.
As mynameiscalypso has said, I would be absolutely crushed if anyone around me now decided that this was the best way to relieve any way that they were feeling, especially if they had seen that I had done it and got the idea from me. It is not normal healthy behaviour.
Like any other negative behaviour, if the person doing it can find a way of rationalising it, normalising it, and belittling it, it can then become justified. It's all a cycle really.
There is so much more help available now though, even if you have to be on a waiting list for it, (she says having just been accepted for another round of talking therapy), and even the worst scars can usually be covered by make up or tattoos etc. so it really doesn't need to be 'sod it, I've already got scars so there's no point in trying to stop'. There is always a way to stop a behaviour like this, and a way to make a 'fresh start' if you would like to?
I'm in the process of planning various tattoos, including a beautiful sleeve which will cover anything untoward from my past. I will be proud to show it off (not that I've absolutely hidden my scars away for a good while now but I am always conscious of them and will wear long sleeves in certain situations or now how to hold my arm to hide the worst etc.), it will be a fresh start...
Please don't give up, it doesn't have to be like this xx