Yup, those rings are pressed on not welded.
In about 1982 my 69 GTO driver side axle came loose, I took it out, replaced the the bearing and retainer. Nine months later it happened again, that time I replaced the axle as I should have done the first time. Sometimes one looks at the cheapest and easiest to fix as the probable cause, rather than facing the reality that the more expensive fix is the way to repair. Perhaps yours came loose way back when and was just welded on rather than fixed properly. Works in a pinch to get home as long as a proper fix is done then.