Why are companies advertising against companies?

[♦Violet♦]

What I mean is, I remember from when I was a child, advertisements never "mentioned" a rival company.
Eg. They would say "brand X" is not as effective as our product.
But now I see ads and they are like "brand daffodils" is useless, ours is better!
Have the laws about that changed?
But I'm telling you they DO use the actual name.
I was watching a painkiller ad for Advil and they flat out said "Advil is better than neurofen"

[Lulu]

The name of the brand 'X' is never shown because it is copyrighted and cannot be used in a commercial or ad without permission.
:-)