I have to disagree with this statement. The difference is although this information has to be entered, one is stored in an account and the other is not. Many customers feel that creating an account with their personal information "stored" somewhere poses a security risk or hassle and turns them away from a sale. This happens whether its Paypal used or not.
I certainly understand this as a customer. I'm sure that most of us have purchased items online and have seen that some vendors require you to set up an account with their store before allowing you to complete your purchase. I don't know about you, but this turns me off unless I just can't get that item somewhere else. There's really no reason for that vendor to hold on to your personal information except for their convenience. The better vendors in my opinion provide you with an option to create an account or skip it. What I'm describing here has nothing to do with Paypal, it has to do with the customer's experience and their perception of what is taking place.
For example, a wonderful company I often deal with is B&H Photo which happens to be the largest photography gear retailer in the nation. When you make a purchase on their website it gives you the option during checkout to create or login to an account, pay with Google checkout, or skip login and pay with a Credit card, Paypal, Google, or money order etc. The orders can be even tracked without creating an account with them. I happen to have a PayPal account, but I do not create an account with B&H to use it, or is it even necessary for me to create a PayPal account for me to pay for the item. This is a great customer experience. If the customer purchases from this vender often and wants to create an account so that future purchases are quicker and so they don't need to reenter their information every time, that is purely up to the customer.
Any company that creates the perception of placing its customers first will always have an edge over those that do not.
I happen to like this software and the ease of use. I purchased it and I think it’s a great product. However, I cannot use it because of this issue and its potential to drive customers away.