Re: The poor advertisers...
"I may have little sympathy for the advertisers"
Your sentiment is misplaced. Ask yourself, who pays the advertisers?
When you think about it you'll realise that ultimately its the unsuspecting user getting stung, all the time. Advertising is just a business expense for retailers, suppliers, builders, etc who pass the cost on to us.
So also ask yourself how ethical is ad funded software and online services? Before you answer that, consider these points:
* The likes of Google are perfectly happy for this type of fraud to take place, they cream off the top every time. In fact, Google have been particularly effective at inventing new services (maps, search, mail, etc) specifically for creating new avenues for adverts. Businesses then have to take up advertising on those services for fear of falling in the public conciousness and losing market share. And every man, woman and child has to pay for that no matter what phone or computer they buy.
* The whole of the UK advertising industry is worth £14billion per year, about £600 for every wage earner, and about half of that is online digital. That's about £300 per year paid to companies like Google by every wage earner in the country. And every time a company like Google invent a new service, that figure goes up.
I think the answer is that it's not very ethical at all. There's already way too much advertising, we can hardly be more advertised at, yet we all pay extra for it without the option.
Worse, Google don't really pay any tax anywhere either.
So Who Owns Google?
That's also a worthwhile question. Google, Facebook, etc. have shareholders, and ultimately shareholders tend to be a small number of individuals and financial institutions who are themselves ultimately owned by pension schemes. That's right, some of that £300 per year in the UK is going into funding foreign pensioners, without it being taxed to help support the UK population first. Terrific.