A Legal Question_Criminal Case

I have a question about the prosecution of criminal cases. Why is it that DA’s fail to charge a defendant with only a small fraction of the crimes he/she may have committed? for example, a murder here recently-Mr. A went to Mr. B’s home and killed him (some dispute over drugs).Anyway, Mr. A then trashed the house and packed up Mr. B’s body in a garbage bag, and hauled him to his house. There, he dismembered Mr. B, and drove to a rural area, where he dumped Mr. B’s remains in a swamp. He then cleaned his trunk, and went back home. He was later caught and charged with murder, 1st degree. my question: why wasn’t he also charged with:
-illegal transport of a corpse
-illegal disposal of a corpse
=descration of a dead body
-breaking and entering
It seems to me that the prosecutor could easily get this guy convicted on a host of other charges-why just restrict it to murder?
Can some prosecutor help me out?

IANAL, but the first thought that occurs is that prosecutions cost money, so I suppose there might exist some thinking to the effect that putting Mr. Bad Boy away for the more prominent offense(s) might be the most cost-effective approach.

Besides, there’s really no practical difference between life without possibility of parole and life without parole + 10 years.

One reason that DA’s don’t include the lesser crimes is to avoid giving the jury an ability to cut a defendant some slack. A divided jury given the option between murder and acquittal, wont let the guy walk. But give the same jury the option of a reduced charge like manslaughter or assault and they will cut the perp more of a break than he deserves.

I would also think there’s some double jeopardy issues. For example, supposed the person was acquitted on the charge of murder. You can’t get him for that anymore, even if you find damning new evidence. However, if you had never charged with some of the other offenses in the first place, and you have new, solid evidence about them, you could then bring those charges up.

(But I could be wrong, since I have no legal training.)

How do I break this gently? You’re wrong. All charges that arise out of the same course of conduct must be made at the same time (with limited exceptions). There are two reasons for this. First, if a prosecutor has a weak case, he/she could hold seperate trials for each charge, hoping eventually to find a jury willing to overlook the holes in the case.
Second, the defendant would be forced to reveal case strategy and (possibly) testify in the earlier trials, giving the prosecution an unfair advantage in later trials.