eCommerce UX Question

I’m currently building a site which is going to be selling software, the pricepoint is around $100 and while there are lots of different bits of software available, users are unlikely to want to buy more than 1 item at a time.

Based on that, is it wise to eliminate the shopping cart?

So for example the user path would be

Product Page > Login/Register > Payment

Rather than

Product Page > Shopping Cart > Login/Register > Payment

Does the hassle of going through the entire process twice for some people, out weight the benefit or removing 1 step for the majority of users?

Or is there any sort of compromise?