On the credit card question, these already exist - they're called Corporate Purchasing Cards. The reason credit card companies don't do buckets is, as Steve all

On the credit card question, these already exist - they're called Corporate Purchasing Cards. The reason credit card companies don't do buckets is, as Steve alluded, the merchant data isn't granular enough and in order to place restrictions on what cardholders can buy you have to know the bucket type of every item that merchants sell. That's a huge problem which even the best Corporate Card companies have trouble solving. American Express is #1 in terms of data but the cardholder often still needs to explain which bucket the purchase goes into. (One reason you need a special POS cardreader for Amex is to inform the Purchasing Card transactions which bucket to use.)