The only time I think it makes fiscal sense to ignore a sizable portion of your potential user-base is when you're already making so much money that the potential income from those users would be negligible.

It seems that the average number of page-views for all sites that are ad-blocked is something like 9% (and on some sites up to 50%)[1].

would you really want to sacrifice a 9-50% of possible revenue?

[1]https://www.quora.com/What-is-the-percentage-of-Internet-use...