I had this discussion around here yesterday. My take, allowances aren't intended for people to make money off of, they are intended to offset the costs of living/eating/etc. As the system currently sits, people are reaping the benefits of dual-mil couples, roommates splitting rent, etc. In the end, if the military says that people are no longer going to rate "making" money off of an allowance, I can understand why. If someone wants to get married to another military person or split rent with a roommate, they may have to factor that in to their budget.
A good point was made by the guy I was discussing it with though, his take is that the whole point of having BAH/BAS, etc, is to simply reduce the retirement costs at the end since it's not a function of base pay. That opens up a whole different debate on the compensation we get and how it's packaged.
Similarly, the per diem rules have changed to 75% of max allowable if you stay in one locale over 30 days now, and that was to limit how much people are pocketing as per diem wasn't intended for people to make money.
I wouldn't be surprised if the military goes back to the old school way of turning in your lease to show the costs, similar to OHA, etc.