Did you ever notice that little kids pull things apart all the time. It gets exhausting putting things together, only to have the "little darlings" tear it all down. Makes me want to stop helping my friends by watching their kids.
Turns out "destructive play" is both normal and educational. Kids learn an enormous amount before age 5.
It still makes me bonkers, but at least now I know the behavior serves a function. Bugger all if I'll ever get into "pick that up for me!" game.