Sneakylong
I'll concede that I mostly agree with just about everything you've written. With exception to the first statement.
I can give Anna the benefit of the doubt in her situation, for the simple reason that I believe she had no idea that she brushed a few grains of sand, and not even a playing partner observing from a mere 10 feet away could've possibly picked up on that penalty. Yet having said that, even at our levels... the more competitive types among us anyway understand that there is a penalty to be assumed should our club make contact with the slightest bit of sand during the backswing. And for that very reason, most of us (not all, but most) make a concerted effort to ensure that we're hovering the club above the ball/sand high enough to not potentially run afoul of that specific rule. So to some extent, I ultimately find her at fault for not being more careful and mindful of that particular situation and allowing herself enough leeway to ensure that she's not touching the sand on her backswing.
And with Lexi...
This goes back to what Mickelson said shortly afterward when he initially commented on her penalty. And really, it also applies to Nordqvist as well, albeit to a lesser degree.
"Rather than address that specific instance, what I would say is this: I know a number of guys on Tour that are loose with how they mark the ball and have not been called on it," Mickelson said. "I mean, they will move the ball two, three inches in front of their mark, and this is an intentional way to get it out of any type of impression and so forth and I think that kind of stuff needs to stop."
An observant playing partner could've easily noticed that Lexi replaced her ball in the wrong spot behind the mark. And even had the playing partner observed this, it doesn't necessarily mean they would've called her out for it. But in this particular instance, if they had immediately brought it to her attention - then all of the brouhaha afterward is likely avoided, although granted there would be another potential boondoggle with the perception that a playing competitor was somehow trying to exert some negative form of gamesmanship.
But there's absolutely, positively, no denying that both Anna and Lexi were careless with how they proceeded. In both instances a rules infraction occurred.
If you want to have a discussion about the harshness of such trivial breaches, then that's ultimately a different issue altogether. I would add, however, that in doing so would require weighing intent, which although might seem easy to do on the surface - is endlessly complicated in general practice.
Seve Ballesteros, as great as he was back in his prime, was one who always pushed the envelope to obtain as much of an advantage as he could. He had a reputation, according to some, of going beyond what would've otherwise been deemed reasonable. So knowing that, how could one remotely weigh "intent" with any reasonable degree of rational judgement?
Players have become to lax, in what would otherwise appear to be the most mundane of situations even. So why not hold the player to a higher standard versus changing the rules to accommodate a notable degree of indifference in a lot of these situations?
Just posing the question out of a genuine desire to possibly be convinced that the way I'm looking at these type situations isn't practical. Unless the rules themselves are relaxed to the point where a lot of this type of stuff becomes an acceptable standard of play, I really don't see an easy solution otherwise.