For me, it is always spamming. I do not like to thrust website URL on other platforms just to gain traffic. I do not like when people to do it to me, therefore I do not do it myself.
That is not always helpful. You need to be forceful sometimes. Trick others, take advantage of the time when forum staff is not watchful and so on.
But I do not worry about it much. My only focus is - am I posting anything useful . As long as the answer is yes, I keep writing, because I got a lot of help in my life from many good people.