I think you probably put your finger on the rational driving force here.

If you can't/don't control the borders anyway... It might be more rational to just go with that and enable official channels and/or rules to work.

Insisting on the impossible, or the not-going-to-happen... It's a mistake politics makes regularly. Policies are only as effective as you can make them.

Anyway, if Kenya is in then this is a serious thing.