I have seen sites die due to too many scripts even after adblocking.
I have bought from companies advertising on the internet, I see the ad I contact the company and I buy the item.
These ads are simple animated gifs with a few seconds per frame and about 3 or 4 frames, banner ad as as well.
And it would be impossible to boycott the companies without changing hobbies.
Yes the forum financed by ads from companies supplying the hobby the forum is for.