Tent - Passive intake - Light leaks?

I've just been wondering, it seems like every single grow tent relies on those small passive air intakes, but those have light leaks. So, is this a massive oversight by tent designers? Or do light leaks not matter that much? Or is it just assumed that everyone will use some home made light-proof intake duct?

It just seems odd that you have to macgyver some solution.

If you have a 6"exhaust duct, use two 6" round passive intake ducts at the bottom, that's what the round holes next to the screened rectangular vents are designed for. Use a short section of duct with a curve, duct filters on the ends.