I would say that it depends upon your sense of obligation really, but that there IS no requirement.
My personal stance, evolved over the years, basically allows me to do anything short of blocking ads. The cost, I have decided, for accessing ad-supported content is the open-mindedness that while I will subconsciously ignore almost every ad on the web, that I am mentally open to the possibility of being intrigued by an ad enough to click on it.
It seldom happens, but not having blocked the ads, the fact that it happens ever gives me a clean conscience.
My personal stance, evolved over the years, basically allows me to do anything short of blocking ads. The cost, I have decided, for accessing ad-supported content is the open-mindedness that while I will subconsciously ignore almost every ad on the web, that I am mentally open to the possibility of being intrigued by an ad enough to click on it.
It seldom happens, but not having blocked the ads, the fact that it happens ever gives me a clean conscience.