ProSites - Adding a second site

I am a bit confused.

I have it set so there is no checkout on sign-up. Hence I do not get the pricing table by pro-sites. Just the sign up option. However, when the customer tries to add a second site, it gives the pricing table. Shouldn't it just let them sign up for a trial blog, the same way they did the first time around, without having to choose the pro-sites option at this stage?