it does not make much sense to cancel a date to replace it with another one. i think of tickets issued, insurrance and all... even if the stadium is not full, why would they cancel one date to replace it by another... just to have 5,000 more people in it? It must cost the Stones a lot of money for cancelling a show! and is it really worht it?
their cancellations will pretty much be covered by insurance
problem is that if they reschedule all 15 shows after August 29th, the tour will run into mid October. Not an easy time to get stadiums in Europe or even rely on decent weather. The more shows they postpone the harder it also is to reschedule hotels, etc. Try finding 4 and 5 star accommodation somewhere like Spain in the height of summer for 300-400 people at 6 weeks notice, for example
So, if they have a small time frame to reschedule a lot of shows and some have to get cancelled its more convenient to reschedule a show that has sold 50,000 tickets than one that had sold 20,000.
Its a logistical nightmare rebooking stadiums and 5 star hotels etc. They should go back to playing in bar rooms and pubs, then go home in the van after the gig, like a proper band.