fixes #598

Ok, so here's what happened.

There was a change I made at the beginning of September to fix the price bump code.  When a group badge is claimed (or under a couple of other similar circumstances although that's the main one), we drop the old badge and make a new one.  In order to make sure that those badges show up as having the same price, we keep the ``registered`` date the same.

So without looking too carefully, I added some similar code to this function, and apparently didn't test it very well :(

This code is totally unnecessary and caused this problem, so I just reverted this code to how it was before.  I repoed the bug, made the fix, and confirmed that the bug went away.