Greatest hits albums: yay or nay?

Let me start off by saying I have a few greatest hits albums and have some on CD as well. But overall I think record companies end up screwing themselves and their artists by releasing these albums( mostly with no warning to the artist or much collaboration with the artists).

Sure they can be useful as a gateway for getting someone interested in a band (it did for me with Testament). But often that ends up being the only one the consumer gets. That's a problem for 2 main reasons. The first is that means the consumer isn't buying the studio albums which obviously negatively impacts the label/artists (most importantly the artists). And second, the consumer never hears the songs on the studio albums (which a lot of times they are better than the "hits".

Best of compilations are usually better because the songs chosen aren't driven by the songs that got radio play. These generally get input from the artists. But not always.

Some bands have never had greatest hits albums released ie AC/DC. While quite a few have several: Motley Crüe, Van Halen, Iron Maiden, Megadeth, etc.

Once in a blue moon tho a greatest hits is necessary for situations where the material the artist released was on singles because albums weren't common: Johnny Cash, Ray Charles. Also if there are previously unreleased material ( not demos, those are usually dreadful anyway).

But generally I skip over them as I want everything the artists put out and if I do then I have no need for the greatest hits.

What do you think?