I did a lot of homework on it- and surprisingly realized.
Foam is useless
Foam does nothing
Foam is a waste of money
You need ACOUSTIC PANELS not foam
And they're not that expensive
The foam isn't worth the paint on the walls your going to destroy with them
Not to be argumentative, but foam is not useless, it clearly does "something" and may or may not be a waste of money.
If by "foam" you mean packing material, egg crates, slip sheets and the like, then I would agree with you that it is not a very effective acoustic treatment. If you are implying that all foam is useless, then I disagree. Many professional ACOUSTIC PANELS are constructed from high density foam. A preferable treatment would be rigid fiberglass (due to the increased density), but many commercial and "home" studios use acoustic foam panels. The panels I put in my studio are "acoustic foam panels" and they are constructed of high-density foam. The shape of the panels contributes to breaking up standing waves, flutter echoes, and the "reverb" effect of the bare walls. The foam is available in various sizes, shapes, and densities to meet a variety of room treatment needs. I have seen this material used in countless large venues and recording studios all over the USA. Most of the professional studios I have recorded in have bass traps in the corners. They are constructed of foam.
Any material that reduces the sound energy does "something" to improve the clarity of the sound in the room. It may, or may not be sufficient to address the acoustics of the room to make it a more suitable recording environment, but to say that it does nothing flies in the face of physics. The acoustic foam panels I put in my home studio made a yuge difference, especially for live room recording such as vocals, and acoustic instruments. I have recorded all sorts of acoustic guitars, violins, hand drums, kalimbas, flutes, and vocalists in my studio, and get commercial quality results.
As I said, Jeries, not to be argumentative, but your post left the me with the impression that foam acoustic treatment is useless and a waste of time and money. Perhaps I misunderstood the point you were making, but foam treatment is used all over the civilized world to address acoustic issues. If you were cautioning the OP not to use cheap foam as a substitute for proper material, then I'm inclined to agree.