I've done a bit of both, and I can honestly say that the biggest problem with freelance work is that your work is short term and well defined.
I don't know how many times I could see client's problems, which weren't always what they thought they were, without any mandate to fix it. Sometimes they even hire you to do something that completely fly in the face of what they need. That's not fun.
If you're in it for the long haul you can allow yourself to take bigger risks, even if it's officially outside your responsibilities. What are they going to do? Fire you for fixing stuff? It is simply a more fun way to work and to interact with your peers, even if it may not be as financially rewarding.
I don't know how many times I could see client's problems, which weren't always what they thought they were, without any mandate to fix it. Sometimes they even hire you to do something that completely fly in the face of what they need. That's not fun.
If you're in it for the long haul you can allow yourself to take bigger risks, even if it's officially outside your responsibilities. What are they going to do? Fire you for fixing stuff? It is simply a more fun way to work and to interact with your peers, even if it may not be as financially rewarding.