Many of these could just as easily be the result of really bad UI design, especially when there are "technical constraints"—the RyanAir example in particular reeks of an opt-out being jammed haphazardly into an existing form to avoid adding another control.

Hanlon's Razor, yadda yadda. These patterns aren't any better if they're accidents, of course, but there'd at least be a chance that the offending company would fix them.