Do you mean because it's too "dying as a career move"? Sorry if that phrase sounds insensitive in this context -- but I've seen it applied to people like Elvis and Jim Morrison, people whose popularity shot up after they died.
No (or yes?), well anyway - mainly because they're buying because
Heath is dead. And those 3 words are just so wrong and grieve me so much and depress me like all hell, no other way to put it.

And further, because I get the whiff of painfully ugly commercial "act to grab the bucks while the body's still warm" - the retailers cashing happily in on the interest surge created by the dreadful and horrid speculation and tales that the media kept going the first few days. Stopping at nothing to gain another buck. So on the side of the buyers I couldn't help feeling there was an element of morbid curiosity. I.e. if they were not invested in Heath's films before, they're now acting on the basis of 3 days of "drugs and substance abuse and pills strewn about and found naked in bed and mysterious Olsen twins connection".

I feel resentment bubbling up at that.
These are not very rational thoughts. Nor very kind to the buyers, who may be just as distraught as I am. I'm the first to admit that. And it's only one part of my reaction anyway, as my previous post showed.
I agree with what others have commented - people probably are buying the comedies because they want some joy as comfort, in contrast to all the media ugliness.... and people are buying the Heath films they've not alredy got. And I completely agree with this:
Anyway, in this case I see it as positive that people are taking interest and maybe opening their minds a little bit, and in the process helping Heath's legacy live on.
"10 things I hate about you" being on top of the Amazon list somehow made me dare to watch this. It's Heath singing
I love you baby in that film, so beware before clicking the link. But I *could* actually bring myself to watch it, and it's so sweet although painful - and I couldn't have done that just one day ago, so I'm starting to process this in my mind, it seems....

Anyway silly as that sounds, the song's title is not entirely inappropriate for how we're feeling now.