you can't and I'm fine with it prevents abuse of sacrificing cheap characters to each other in the pit to amass a fortune early on
and power grinding
You're for it when it comes to people not boosting but I'm sure everyone would agree a practice mode with no experience points against friends would be a good idea. The idea of not playing with your friends is just stupid. Everyone should agree on that. It's how you set it up so people don't boost.