Doubt Lexi intentionally caused that penalty.  Also, remember watching the tournament where Nordqvist unintentionally caused movement of a grain of sand while in the bunker.  It was literally a grain of sand.
Nordqvist handled that incident with class and professionalism. 

As to the statement "penalty doesn't match the crime", it certainly rings true when a grain of sand is "caused" to be moved.  Everyone is, of course, entitled to their opinion about the four stroke penalty imposed on Lexi.  

What everyone should be saying is the rules need to be changed.  Given the penalties imposed over the years, many of which seems a bit ridiculous in hindsight, you gotta ask why weren't there changes made to the rules of golf.  Maybe it's time to finally get this done.

Let's remember that while Dustin still won his tournament, it often meant losing the tournament, or at least the chance to win.   And let's also remember that someone did end up winning those tournaments, and deservedly so.