Why STW doesn't service all areas covered by T-Mobile?

[Fearnoevil]

I recently decided to switch from Sprint to T-Mobile because they now have excellent 4G LTE coverage where I live in Riverside, IA. But a friend told me that I could get cheaper service using Straight Talk Wireless because they use the T-Mobile network. But the STW site is telling me they don't provide coverage (map shows no coverage at all). Why is this the case?

[ST - Larry]

Hi Fearnoevil. My name is Straight Talk Larry. For further assistance, please check your forum inbox for a message. Click on "New Messages" beside User Control Panel to view your forum inbox. Thank you.