Yes, but we tend to collaborate with members of our own species and enslave/butcher/experiment on other species. Even our relationships with dogs and other family pets can be highly unequal and sometimes downright disturbing. (Treating them as chattel, "putting them to sleep" when it's more convenient to do so.) So this counts against your position in two ways: 1) our only data point indicates that interspecies collaboration is likely to be less than cozy 2) others might observe our treatment of other species and use that to evaluate our potential for hostility.
Also, our record with regards to polluting our own environment doesn't recommend us highly as "good citizens of the galaxy." (This was brought up as a possibility in David Brin's Sundiver series.)
And this isn't even considering the vast differences in culture and even basic mental models there will likely be. It's far from a sure bet that this openness will extend to us.
Also, one can readily imagine how a "innocuous" act from the point of view of one species might be considered a greivous crime by another. (The Ender's Game books are one example.)