"but I often cross borders and am not checked"

Look in a mirror. You might see a very similar sight than me: white, tall, middle aged without a Britney Spears or ACAB face tattoo.

Just like @nprofile1q... I often don't get checked personally (and just like him I often remind them they forgot all the non-brown people).

But others are. For example on the Flensburg - Kolding train this week. Of the ten passengers eight were completely ignored. The two "spanish looking guys" got checked. They were Danish.