This will not be corrected as noted. There are two issues occurring. One, Sprint launched early long before they have comprehensive coverage over the market. There are so many sites live, they might as well allow customers to use what is open.
Two, Sprint's LTE devices are set for too high of threshold to connect and stay connected to LTE. The device will shunt users back to 3G if the 3G signal is strong, or if the LTE signal is too weak. Sprint needs to get with their device OEM's to lower these thresholds. But this would require an OTA.
Robert