Jason,
What is your definition of "snug"? A frame package should sit on the wall with some space behind it to allow for air circulation behing the frame. This will minimize the formation of mold/mildew on the back of the frame package and the wall and allow proper air circulation around and within the frame package as environmental changes occur in the home. If you mean tight against the wall, that may be too snug.
With WallBuddies, the hangers will keep the back of the frame away from the wall approximately the same space as the bumpons at the bottom of the frame. There are hundreds of framers that use the WallBuddies system now and I think that one of the big selling points of WB's is the fact that they are a very positive method of hanging. By that I mean, after you level the frame package on the wall using WB's, (they are self-levelling, BTW) you won't have to worry about going back later to level the frame from misalignment caused by wall vibrations or door slamming. My customers love that convenience and I have had a few bring their entire art collection in for refitting with WB's after they saw how stable the are on the wall.
But your problem may stem from the fact that you are trying too hard to get the frame closer to the wall than is necessary.
Hope this helps you.
Framerguy