Steps to reproduce on win7 x64:
Take latest build JRE8 64 and 32 bit (both)
1. Install 32 bit JRE
2. Install 64 bit JRE
3. Open Control Panel->Programs and Fetures
If you see one installed JRE bug reproduced.
4. Uninstall JRE from Programs and Fetures
5. Check both Program Files directory
If you can find JRE from one of directory bug reproduced.

Expected behavior:
Both installed JRE should be in "Programs and Fetures" list and after removing should fully remove file from c:\Program Files*\Java