convert your bitcoins into cash immediately, which if your doing that then whast the point, just sell them for cash to start with
the point is not everyone has a credit card, or even if they do have one, not everyone wants it connected to their purchases.
there have been so many times lately where i've been to a site and really wished they accepted bitcoins, because for me, they're 100x more convenient.
example:
http://rapidxhtml.com looks like a great service, but completely useless to me because they only accept paypal.