You're confusing "most people want" with "privacy violation".
You're making an "all-or-nothing" mistake, repeatedly.
Privacy can never be all-or-nothing. Leaving one's curtains drawn or leaving one's house increases the risk of being photographed, but I still recommend doing both. The trick is to get risks and violations down to acceptably low levels.
How low can you go? Depends on how much inconvenience/effort/cost you're willing to accept. In general, there's a law of diminishing returns, so it's best to make some effort to reduce risks somewhat in all aspects of life rather than putting a lot of effort into getting a small few problems down to zero.
If there are [Firefox tiles] you don't want showing up there [in new tabs], you can click the (x) on the thumbnail.
Great. Solution after the fact.
No. Wrong, wrong, wrong. It's a solution to all but the first occurence of the problem. If you open a browser a thousand times, but you click (x) the first time, then I've reduced the problem by 99.9%. If you can't see this then you don't understand privacy.
99.9% is acceptably low for most things. Do it, and move on to the next problem. Don't dwell on the 0.1% - this is time wasted that could be spent on reducing something else by 50, 90, or 99.9%.