If it belonged to you and you offered it for sale and people took it without paying for it, would you call it stealing?
I think you would.
My father taught me that lesson long ago when I was a little kid. Whenever I stated doing something that wasn't right, he would ask me if I thought what I did was wrong.
If I started rationalizing it or coming up with excuses, he would tell me to put myself in the other guy's shoes and see if still I thought it was OK.
I almost always changed my mind