I haven't been keeping up on all the new NEC requirements for shoving xxCI's in various places, but I can see no rationale for this one. There is no such thing as 240 volts to ground in a home - it's all 120V (that's RMS, it's 170V peak), with a "240" outlet being both line phases (say +120 and -120 at a given point in time, giving a differential of 240).

Touching a residential "240 volt" line for a dryer or stove will give you the same exact shock as touching a common 120 volt line. The risk of 240 volt circuits is that they are generally of higher ampacity, and will thus have a much higher arc current. A GFCI does absolutely nothing to mitigate this!

Honestly they would have been better mandating the garage 120v receptacles be GFCI even though they're above grade, because people tend to do things like plug extension cords into them for use outside. 240 volt receptacles generally have a dedicated purpose, like a car charger.