Do you know why NFL trade rumors are running wild during a lockout?
Do you think that team general managers are sitting behind their desks for 40 hours a week becoming the greatest solitaire players of all-time?
Let's answer those questions in tandem. GMs are still getting paychecks because they are not locked out and are working. They are also not prohibited from speaking with other general managers about "stuff".
So, what are they working on?
They're working on player transactions and acquisitions and contract framework.
How do I know?
I'm a realist and I'd be foolish to assume that these front office people are sitting back in a chair in an office somewhere half asleep with their phone on "Do Not Disturb" or email with an "Out of Office" response.
In fact, it is insulting to all of us that the league would like us to think back-alley deals are not being discussed between teams. Like I said, just because the non-union members of the front office can't talk to the players doesn't mean they can't talk to each other—and they're not asking how the kids are doing.
All of the aforementioned leads to the possibility of leaks, and leaks develop then into rumors.