This is certainly subverting the domain name system. I can't see the value or gain in security by this.
(If you want to put focus on the domain, then display the host-part with less contrast, i.e. grey, but don't hide any potentially vital information. Otherwise, put out a RFC, defining "www" as a substitute for "*", or a zero-value atom, in order to guarantee consistent behavior.)
Edit: There are also legal concerns with catch-all domains in some countries. Blending the lines certainly doesn't help.
(If you want to put focus on the domain, then display the host-part with less contrast, i.e. grey, but don't hide any potentially vital information. Otherwise, put out a RFC, defining "www" as a substitute for "*", or a zero-value atom, in order to guarantee consistent behavior.)
Edit: There are also legal concerns with catch-all domains in some countries. Blending the lines certainly doesn't help.