Ive seen several complaints about them charging your card before they actually ship. It is foolish and a sure way to fail financially to do otherwise.
Ex: Joe Blow orders and upper and gives you his card number. You build his upper then go to charge his card and he has no money. You're on the hook for materials while he gets his his finances in order, if he ever does. You're suppliers expect to be paid on time or they cut you off. They dont care that Joe Blow lives paycheck to paycheck and manages his finaces poorly. It only takes a handful of Joe Blows to put you out of business.