Do I think it tasteful, nope.
Do I think it will sell lots of magazines, yep.
Do I think the British Government can stop it:
an Italian publisher is publishing pictures taken in France of the British Royal family in an outdoor setting. Nope
Not sure how the Royal family can put those associated in jail. I would recommend that they dont go to England any time soon, but I dont know of any laws broken, (I am not up on my international l laws so YMMV)
Do I think it was poor judgment for the Princess to be outside and topless? I will let Prince Harry answer that question