Ahoj David! I respect your opinion, but allow me not to agree with you.
All over the Schengen zone, those points have been removed on OSM because they are not permanent (there is a notable exception: when driving from Šalčininkai towards Dieveniškės within Lithuanian territory, there is one permanent control post
Intra-Schengen controls do not necessarily take place at former border posts. They usually take place in completely random places. Hence, mapping them makes no sense, just as mapping police control spots doesn't make sense on OSM unless they are permanent. We've got apps like Waze to signal when there are some customs/police/border controls in such places ;) 
Regarding knowing a place where you are leaving a country and entering another, well ... you already know it by looking at the map ;)
Have a nice day!
Na zdráví!