Please, please, please never, ever put your dog on the floor by force in the so called "Alpha roll". This has no grounding as a behaviour altering method and, with a truly dominant dog, can be highly dangerous - if the dog is truly dominant, if it really is making a challenge for leadership rather than having the role forced upon it, then this is the quickest way to get your dog to bite you!
If your dog accepts this treatment with only a struggle then your dog has had it's Alpha role forced upon it and does not know how to cope with it. A truly dominant dog will have your face for breakfast if you try this.
BeBe is not a truly dominant dog, his behaviour with treats will not lead into aggressive behaviour in other areas as long as you stop putting him in a position where he has no other choice than to defend his food.

Many trainers advocate the Alpha roll - it is a good way for owners to feel physically superior to their dogs and it is a definite position of power. The dogs that allow you to do this are not really dominant dogs although they show some dominant traits.
A dog that is really, truly, an Alpha type is very rare indeed. If you have one then it would not allow you to put it on its side or back and hold it there against its will - you quite simply would not be able to do it.
It is a false belief that you are doing anything to change the status of yourself or the dog by doing this - wolves, quite simply, do not behave this way to establish or maintain dominance.
The behaviour is highly ritualised and is only displayed in highly defined situations - never as a serious Alpha changing behaviour!