They pirate or already subscribe to Crunchroll. Many sites are nowhere near brand safe (one reason Danbooru is as good as it is that is not even brand safe for porn ads.) Some of them buy figurines, but they already know where to get them. Good smile would rather invest in 4chan than buy ads on western anime sites. I have no idea what it is like in Japan.

I am skeptical of claims that “advertisers want to target young people because they have a lifetime of consumption ahead of them”. Maybe that is true of Proctor and Gamble (who expect to still be selling Dawn and Tide 50 years from now) but few advertisers are thinking ahead more than one quarter, if that —- particularly in the internet age where an ad click can be tracked to a transaction.

People today will say all the ads on TV target oldsters because only oldsters watch TV but circa 2000 there was no streaming and watching TV made me think “I want to die before I get old” because there were so many ads for drugs and embarrassing health conditions and personal injury lawyers and relatively little for things you would spend your own money on because not a lot of people in the audience have money to spend particularly after paying the cable bill.