How heavy is too heavy for an IEM rig?

Components that are a kilogram here, 500g there, 3kg here, all start to add up and suddenly for a 5 piece you're hauling 35kg of kit up three flights of stairs in a pelican by yourself (because the vocalist is busy talking to girls, the drummer has their own problems and your guitarist is MIA).

Flights generally seem to cap you out at 32kg per piece of luggage but it has me wondering what people do then their rig weighs like 60kg on its own.

How heavy is too heavy?

What do you do to keep the weight down?