That's a fairly convenient justification. You "ask for something"? How do you think the provider of that "something" has the means to provide it?

You should be thankful that people like your grandfather exist, such that they can subsidize your ad-free internet experience.

Legally you may be correct that it is not stealing, but at best you are altering a copyrighted work with out permission. Here there are a lot of web based businesses with money on both sides of the advertising game, so I will actually be surprised if you find much sympathy.

I agree with you that ads are good for the internet, but I'd very rapidly put myself against the idea of any legal issue with modifying a website on the client. There should be no question that I can do what I like with the HTML served while it remains on my machine - whether that's blocking a popup, removing an annoying advert or terribly placed menu from the DOM or anything else.

Man, if blocking ads is stealing, then walking away from the TV during commercial breaks is stealing too. What if you DVR something and ff through the commercials? Would that make you a thief?

Not by many definitions of the word.

Not that I disagree but Wikipedia has an ad asking for donations once in a while. I would categorize it as fairly obstructive.

Once a year, and doesn't have ads whatsoever.