I raced my miata (spec miata) w/out hub rings.. If the wheels are torqued and you have the proper lugs on there it won't be a problem!

 

I'm 92 years old and I've smoked all my life and I'm still feeling good!

 

I think it's more a case like being 92 years old and drank water all your life and still feeling good. There's evidence showing smoking is harmful - I've never heard of any evidence showing running without hubrings being harmful. To add another data point, I've run my Volks for tens of thousands of miles - street, autox and track - without a single issue.