This is horrible and scary, why border guards are even giving the authority to revoke visas is beyond me. When people think about giving cops/guards authority like this they need to be picturing the dumbest bully from their grade school. That's who is going to be using the power
Every country is like this. Israel is the scariest but I remember decades ago crossing into Switzerland by train and in the middle of the night being woken up by border guards with barking German shepherds asking for my passport. I have so many stories it’s funny. On top of the other stories I’ve already posted, my friend who is Canadian drove into Buffalo for dinner and on his way back, they asked him where are you going. He answered “Canada” and they detained him and pulled apart his car looking for drugs. He was detained for hours until they let him go.