On a wobbly bolt, the seat moves independently of the head and the
shaft, like a large washer. This lets the bolt seat correctly, whilst
still lining up with the bolt hole. 4x98 wheels are rare, and the
majority of Fiats and other Italian 4x98 cars you see around with
aftermarket wheels will be using wobbly bolts. Doing this is completely
safe, no corners are being cut, my issue is with saving a few coins by
putting a standard bolt in with 3 wobbly bolts.