I never once saw that it did, I just tried using it with no credits or payment info and it worked.
I mean it surely dont sound so from their site. More like we still charge you even if you given us nothing and we provided no extra information that you have to pay for anything. I luckly realized it before anything was running for me but it does just seem as a very fishy method which restrains me from using it.
I just thought you might have more information than I could find.
I still dont think it is good to advertise something as a developer which uses so unclear and fishy structures especially when you advertise it as a "for free" stuff while it does not say anything about that on the site. All in all not really trustworthy for me to use.