Ever see a wheel *already* in balance??

[only5kgt@uswest.net]

Weird question, I know.
But I couldn't pass up those 15x6 alloys. Suffice it to say
that, inclusive of two new tires (two were OK) i barely hit
the three digits in this upgrade. Looks good, turns in
nicer, more reassuring in turns. All fine until 80 mph. At
which time, a strong "balance" shake appears in the
steering. Wheels are not hubcentric (Huw, I know, but at
this price I'm playing around here...)
Are there any standard adapters around for this purpose? I
was thinking that they probably have to use them on
aftermarket rim setups... too many possible combinations to
warrant tooling up all those different varieties of offset,
bolt pattern, and center hole diameter.
I closely looked over the tires after the initial trial run.
Nothing odd except that LF tire has *no* weight attached.
Now, has anyone ever got a wheel back from the monkeys this
way *on purpose*?
I'd like to think this has something to do with the vibes.
Aside from that, I can say that if you happen upon Ford
Contour 4x108 alloys, they'll bolt up just fine on
CGT/4kq/5ks. I'm going to try to resolve this final quibble-
curiouser and curiouser.
Aside from concentric adapters- would conversion to studs
have the same effect as a hubcentric wheel fit? (Why,
exactly, is the Audi hub set up for bolts as opposed to
studs in the first place??)
Regards,
Rob