It seems like it would be fairly straightforward to, on a failed launch because of missing java, check for a default minecraft install in the program files folder (with extra logic to check the OS, if necessary), and then grab the JRE from the runtimes folder in there. If all that fails, a popup that simply asks the user where the java installation is could be presented. This is along the same lines as what MultiMC does, though they have their own launcher that isn't java dependent for it's startup, and prompt for java when launching MC.
Yes, it actually is a big deal to me to not install the JRE directly from Sun as it is currently ranked at the 2nd worst security offender behind iTunes for virus attack vectors. Given how commonly mod authors use advertising supported download links that are often fake AV, or other malware ridden ads, I am trying to limit my exposure to potential risk vectors.
I'm sorry to hear that you don't think this adds value for your users. I'll miss using the program.