content: If you need to get paid then probably yes. You can't have it both ways and expect search engines to list you and people paying for the connection to reach you on the public internet and then cry about what they choose to download to their computers on the connection they are paying for. If you have something so compelling that you think you can attract users behind a pay wall then do so and pay for ads on google and make millions. Otherwise if you put your shit on a public network then you can only force someone to take none or all to the best of your technical ability to do so which is pretty much a losing battle.