Isle of Man & VAT registration - bit of a silly query but....

Any reason not to register an Isle of Man Holding Co for UK VAT? I can't think why not but something is holding me back. There will be no trading, save for registration and compliance costs. .?

In brief I have an IOM holding Co with two UK subsidiaries. The UK subs are fine for VAT registration and I am applying for VAT group status to make life easier, but I am not sure if i should register the holding Co aswell.

Am i missing something obvious or just stupid?

Thanks