Since WEEI has 850 and 93.7, they could put the NBA Finals on 850 and leave 93.7 to carry the Red Sox or regular programming. At least Boston will have the NBA Finals. In fact 850 should become the full time ESPN affiliate to allow more sports broadcasts.
Blame Arbitron for this. In order to qualify for "single-line reporting" (AM and FM ratings are combined into a single number), you can't break a simulcast at all - and as long as WEEI is locked in a battle with WBZ-FM for every tenth of a ratings point it can scratch out, it's not going to risk any erosion that might come from splitting off 850. I'll spare Raccoon the need to repeat himself endlessly on this: there are absolutely some parts of metro Boston, especially in the "RF overload haze" around Newton/Needham and around the Pru, where 850 is often the only usable piece of the WEEI simulcast. (And, yes, other parts - like, say, a certain North Shore mail-processing center - where 93.7 is usable and 850 isn't...)