Because they are referenced by name MANY MANY times. And you seem to be the only one who has this particular niggle. Also, I don't think Silver particularly sees any value in allowing players the ability to self-insert.
While that is totally true, I don't think the number of references to that name should count as an argument. He's already using placeholders a lot of times in dialogs, ie:
"Julia looks happy. What's the harm in making my {julia_kate_soft} happy?"
"Julia is my {julia_kate} and my roommate."
"Yes, I go here when I get bored sitting home. The coffee here is amazing. And sometimes I make sure my {alice_lisa} Lisa gets home safely, she's working as a waitress here."
"My {max_to_sisters} Max. You'll meet him if you visit my place."
"No. These aren't mine. Originally they belonged to Ann, my {ann_to_family}."
Introducing new ones could be done with a simple search and replace. But I suppose he has his reasons to not make them variable in the first place.
So you used a tool that is not made nor endorsed by the creator of the game and now you wonder why the save function doesn't work. When you get back into the game, see if the save function works BEFORE using the save editor.
If it does, then it's because of the save editor. If it doesn't work at all, then it's a common problem A LOT of other people seem to have.
There must be something different about my system as I've never had save issues, with or without the save editor.
Also make sure that you have both read and write access to the save folder (and its subfolders) in the directory I mentioned above.
The save editor only does basic file operations in the save game location. If they didn't change the algorithm after 0.22 (it's the last version I tried it with) it should still work fine and saves should be readable by the editor and game. However, of course I can't rule out any bugs in the editor. I'll download the newest game version and see if I have the save issues as well. Right now it's hard to be helpful as I couldn't replicate the bug with the old version.
Cheers,