Fraud and chargebacks would obviously be the main risk points. The credit card companies may cancel payments even in 3-6 months after it was made. By that time of course your bitcoins would be long gone.
Ironically your signature is promoting a platform that allows you to fund via credit cards.
Any service would likely need to essentially make sure that the transaction is flagged as suspicious at the credit card company, have the CC company contact the customer and verify that it was in fact authorized. This would greatly increase the costs associated with not only accepting credit card payments but also doing business as every single transaction would need to be handled manually.