Because there is the potential to glean more and better information from someone who has already had the experience than you would obtain from a phone call to the provider. For example, if the OP or others already looked into this and found out it was some sort of bait-and-switch gimmick. Or, that there were unexpected fees. Or that it was only for a limited time. Or that there were limitations that were only disclosed in the small print when you were signing up. Etc., etc. And now you know.
And how did that work out for the OP of this thread? Did you get your answer after 30 months of this thread being started? No. Not yet at least.