Conduit protects a cable inside a structure; trunking carries cables along a surface and lets you get at them again. That access is the whole difference, and it determines which product a market buys more of.

Markets with a lot of new concrete construction buy conduit, because the cable goes in before the finishes and is never meant to be seen. Markets with a lot of renovation buy trunking, because opening a finished wall costs more than accepting a route on it.

Most containers need both, and the ratio is set by what the local building stock is doing rather than by preference. A buyer supplying a city with an ageing housing stock and a lot of rewiring will move trunking faster than conduit even if the same wholesaler sells both.

Where the two meet, the fittings matter more than either product. A route that runs in conduit through a slab and emerges into surface trunking needs the transition to look deliberate, and that is a fittings question.