If that’s the case they should market the plan’s throttling upfront. “Unlimited mobile data” comes with very clear fine print that isn’t buried in the TOS about how many gigabytes the customer gets before it drops them to 3g speed.
I believe in those cases even after you pass the throttling limit you can continue to transfer data at however much 3g speeds will get you for the rest of the billing period, and thus they won't cut off your service for using "too much".
