Yeah, it's more logic to rob the same item twice, to escort the same guy for the same event, and why not to kill the same guy twice...
More seriously, it's not a MedFan world with magic, resurrection and respawns... But whatever.
Think about it another way: your save is mostly a matter of what stuff you have, the main paths you chose, and what you triggered - considering that you went to the full end of the last version. You really, really think it's impossible to import? Or to ask questions about this? You never used a savefile editor for Ren'Py to see how much it isn't a technical problem?
Ren'Py don't help devs for that, OK, but it isn't a real, huge problem - but it starts to be a problem to break saves when the game is quite advanced. Skipping with "Ctrl" don't work for unread text - and you know that this isn't kept well between updates - OR you need to enable "Skip all" - therefore you'll miss new texts, and it MAY be a real problem if game structure is heavily changed.
But if you don't want to understand, OK. Game is interesting enough to not drop it only because of that, and if it happens only once. But I already dropped games because of that - they weren't interesting enough to replay them, OR they were too complex/long to endure it again.
I play for FUN. Not for being annoyed. If it's not your case, you MAY have missed something...