Note that it's the credit card company that approves/or not - the issuing of the credit card. The bank are the ones that can set the limit.
I got a CCs with different banks, whenever I called Visa/MC to inquire about increasing limits they direct me to call the bank for that.
Ran into a problem with Galicia re: a duplicate I ordered for my wife. Visa approved it no problem, but the Galicia Branch halted the delivery because of some snafu with a debt they claim she has. (there is no debt... when we sold an old apartment, the new owners didn't take ownership of the phoneline, then they defaulted, hence making it appear as it is her debt; proof of sale resolves this... I digress).
The bank is the middleman in all of this.