Oh, in that case you can just connect all your resulting ground wires together to something conductive, and just run one wire from that to your encoder.
For example. Take an old cast off extension cord, cut yourself a six or 8 inch section, and then strip off all the plastic so you just have a section of wire. Take a small piece of wood, and affix said wire with a pair of screws so it is stretched out full length. Then you can solder all your grounds there (or twist them on if you want to be ghetto), and then run one wire from there to your encoder.
But that is actually more work, and more headaches than properly using quick disconnects.
An alternate strategy is to use a combination of splice/solder and quick disconnects. Where each disconnect only has one wire going in, but that wire has a wire soldered on right below it.
Heck, half the time I don't even use quick disconnects on my grounds, I will often just solder my entire ground loop (which is largely unlikely to EVER have to be altered), and only use the disconnects on the inputs.