You are joking, right?
Would you check in to an elegant hotel with a bag covered in bumper stickers? Floral printing? Someone would look eccentric at best--and a potential guest to avoid. All these methods are like dying your hair orange and wearing shabby clothes in Paris or Rome so that a pickpocket would think you were poor or nuts. Forget it. Robbers are opportunists, not logicians or that smart.
I have traveled around the world all my life with practical (and good) luggage. I have never had any bag or any object stolen (even in a bustling railway in India, for example, or in Kabul or Katmandu or Brazil...).
I used to carry jewelry and my favorite shoes and everything needed to look great in Paris or London or New York, etc.
Now, I take chic things--but I always ask myself when packing-'would I be upset if I lost this when traveling' and I don't take my favorites or anything irreplaceable.
I tie a 'twist tie' around the pull rings of the zippers on my bags (hard to untie quickly) and leave it at that.
Good luck with the goofy bag idea.
Obviously, and as I said initially, this depends on the general level of traveling and lifestyle you adopt. I wouldn't go as far as uglifying my luggage, either. But I did put black duct tape over my camera labels and do get less comments and arouse less attention for it.
In NY, Paris, London I go all out, too, in terms of what I wear. Those places are fairly save. Although I have gotten violently robbed in front of my apartment door in Paris, although I took a taxi that dropped my right in front of my door. Suburb kids who come to the "rich" quarters to steal. I have also heard many times of people who were riding the metro late. They get cornered by a bunch of youngsters (gangsters) who tell them "Nice watch" or "Nice leather jacket" and if you are wise you will then part with your Rolex. Sad but true.
My friends in Mexico City told me to be very careful and to take only the most basic of Casio watches. They get robbed at gun point regularly and they don't even look that rich.
Mind you, we are talking about luggage theft here, not general travel safety. I apologize for the off tangent.
Till