You're being biased by the climate in the US. A lot of union rep would give free legal advice to nonmembers, especially for small and common things such as clauses in employment contracts.
In Denmark there are two unions for IT workers: One for engineers and one for IT workers. Both of this have experience with intellectual property agreements and both gives some free help (like looking over contracts) with the hope that you will sign up for the "premium" membership.
I think the best way to describe danish unions are that they are a mix of us unions (that i don't know that much about) and law firms for worker.