I have always wondered about this, since I was thinking of doing the same. I never tried fearing this problem so thanks for bringing it up. But I guess its also cos my awesome feeder is so sensitive to the smell of mice i just need to walk past with a piece from my mouse cage and hes out and ready to strike. I think if I keep my mice near this little guy, I'm gonna get bitten every time I reach in.
But when it comes to being desensitized to the scent and not eating cos of that, I shouldn't think so. For one, ball pythons in the wild usually live in their last meal's burrow but still catch another when it comes along. Another thing would be because so many people have kept them in the same room successfully.