Nope, don't know why, and the reason is likely to differ from one installation of Windoze to the next.
You're not the first to complain about getting an E220 installed, but usually what happens is a forumite struggles and then days later finds there was some application running that was trying to hump the E220 to death - I still think that is what is happening on those notebooks you have there - some application is running momentarily when the E220 is detected and then stops running before you even see it in Task Manager, but by that time it has already interfered.
I have had that happen to me with a customer.