That's exactly what we thought, and so we started a site to allow easy conversion of USD/BTC:
We've been in business for a few months now, and don't want this to sound too sales-pitchy, but our customers all love us because converting used to be such a headache. For payment methods, we don't accept credit cards (for chargeback reasons as you mentioned), but we do accept prepaid debit cards, and we have Dwolla, MoneyPak and Western Union as "instant" payment options.