Flash update force-installing McAfee

Question

I'm writing this as a long-time member of Creative Cloud, a guy who uses (and loves) Adobe products daily, and who has repeatedly boosted and defended Adobe to his sometimes suspicious friends and coworkers. I've built my business using Adobe programs.
Do you want me to stop?
I finally got around to letting Flash update itself on my home machine. And it also installed, *without asking*, some McAfee Security Scan software.
Please note that I do not avoid McAfee like the plague. I avoid the plague like McAfee. And it really, really, really pisses me off when doing a security update on a completely unrelated piece of software forces me to install something - anything - let alone something that I really really don't want. This is not a particularly contentious position for me to take: Hell, even McAfee hates McAfee!
It is absolutely outrageous that Adobe's installer didn't even give me the option to cancel the install. I canceled the whole thing once, and then went and started over, only to confirm that there was no way to avoid the forced McAfee install.
Hey, Adobe: I shouldn't have to choose between having an old version of your software or having to go back into my control panel to excise some crap you forced onto my system without my permission.
I'm not usually one to complain about "corporate BS". I know how marketing works. I save my outrage for truly egregious betrayals of customers' trust. But this is one of them.
Adobe, I hope you're listening to this, because I'm as devoted a fan as you're likely to see. I go weeks without having fewer than two or three Adobe apps running at once on multiple systems. I talk about how awesome your design software is. For the love of God, I went on a rant about how awesome Muse is to a relative who works for Weebly. If you're pissing me off enough for me to wish I had an alternative just because your behavior is so incredibly arrogant and obnoxious that it overloads all of the positive work that the rest of your excellent products have done, then you have a really, really big problem.
You can do better, Adobe. Please do better.

Answer 1

Thanks for the feedback, and apologies for the frustration.
We take these reports seriously, and I investigate the vast majority of them; however, I've been unable to find a set of steps that reproduces the behavior that you're describing.  There *is* a pre-checked checkbox that opts in to the McAfee download, but you should only get the bundled offer if the box was checked.  The intent is absolutely to respect the indicated preference.  If the software did not behave as intended and you received the bundled offer with the opt-in box unchecked, I'd be more than happy to investigate further and try to get the issue fixed.  We test the installation and upgrade workflows carefully across multiple people in multiple geographies using a wide variety of configurations with each release, and I've never seen this issue come up in our testing. 
This is a complaint that I see far more than I would like, which is why I try to be diligent about digging into reports; however, the lack of reproducible steps makes it hard to find anything concrete to fix.  If I can nail it down, I'm more than happy to champion the issue and get it resolved.
I spent a good amount of time recently trying to make this happen for Firefox with no luck using a whole bunch of variations while outside the Adobe network:
Shared Files - Acrobat.com
I do know that occasionally plug-ins that modify how JavaScript on the page gets executed can cause the wrong payload to be downloaded; however, the unmodified code should not produce that result.
If you have any relevant details that might help me reproduce the problem, or see anything that I'm missing (maybe you're doing something differently during the installation, etc) when testing this,
I've provided a copy of the screen that you should see with the opt-out dialog a the beginning of the installation process for reference.