All I have to do is look at my fiance! He doesn't have the same carb-craziness that I do (always leaves the pizza crust behind!), but puts away a package of bacon like it's his job. He's never been outside of a normal weight range, and I have struggled with weight all of my life. Anecdotal, I know, but interesting all the same.
You can't decide whether Bacon or Bagel is worse for you until you know how much of the Bacon is "distributed and stored" (as fat) and how much fat "the body hangs on to" when you eat the Bagel. If Bacon causes 1 gram of fat to be stored and the Bagel causes .5 gram of fat to be stored, then the Bagel would still be the better of the two. For people with an RNY or DS, malabsorption of fat but not of carbohydrates is also part of the equation.
To my knowledge, too much of ANYTHING can make you fat. But I think a bagel takes up too much space in my pouch, so I avoid them. Bacon doesn't have enough protein for the calories, but I do love an occasional Jimmie John's Unwhich with yummy bacon, turkey and cheese!
It's always great to have a GOOD reason to eat bacon.
BTW, if you switch to pastured pork, which you can usually purchase from a local grower at a nearby farmers' market, there is much less fat than industrially grown pork. Yes, it costs more, but you aren't going to eat that much anyway. So why not eat the best you can get?