I'm hoping the data available at the "premium partner" level will come down to the basic users as time goes on, and it's just to make sure nothing is overwhelmed the first week or so.
For those curious, the API limits for basic users:
I thought this way as well, but professional sports leagues argue that their efforts generate the data, so they own it (i.e. without their venues, players, coaches and additional resources, those numbers wouldn't exist). They will allow you to consume that data in approved ways, such as going to see a game or watching it on TV, but they do not allow you to record and use that data for profit without permission. The companies who provide sports data feeds have jumped through a lot of hoops and pay significant fees to license that data. The companies that use those feeds do, too (e.g. fantasy sports league manager services, sports reporting services, sports betting services, etc.)
I'm sure like a lot of other things it's open to a countries laws and interpretation. According Corynne McSherry, EFF's Intellectual Property Director, "It's a fundamental principle of copyright law that facts are not copyrightable" State side something like this should be ok.
However, it doesn't sound like the same protection is afforded in the UK with regards to the English and Scottish Premier Leagues based on the link you provided.
I'm honestly not sure about what is free to use and what is not. If you guys are looking for a free stats solution for MLB, head over to http://erikberg.com/mlb/ .
Perhaps an expert can say whether it is legal to make money via advertisements if you use this data.
For those curious, the API limits for basic users:
>1 Calls per second
>2,500 Calls per day