Age in years doesn’t mean all that much when it comes to aircraft. Consider the B-52H, which is scheduled to remain in active service with the US military until sometime around 2050. (The H is the newest version, which entered service in 1961.) And NASA once declared the airframe of the Martin Mars to be practically “as-new”, thanks in part to having fewer flying hours than your average 10-year-old airliner.
Since my taxes help pay for the Snowbirds, I’m quite okay with using the Tutors for as long as it’s reasonably feasible. If it ain’t broke, don’t replace it with something stupidly expensive. And when the time comes, why not use Hawks or Alphas for the demo team, like others do?
Well why not use the Hawks or Alphas as possible replacements indeed; the BAE Hawk is a fine and nimble plane, well suited to an aerobatic role. Who exactly suggested otherwise? And who suggested anything "stupidly expensive" as a possible replacement for the Tutors? Certainly not me. Re: the F-18 i merely re-stated one possible and oft-suggested option...
Without checking with my air force pal I'm pretty confident in stating the Tutor airframes have a lot more flying hours on them than a 10 year airliner. Remember for their first decade of their life they were front line RCAF training aircraft, flying plenty of "regular" hours training Canadian and Allied/NATO aircrews, on top of the 45+ years now of extreme air demonstration flights.
And unlike a Tutor a B-52 doesn't pull off the same extreme manoeuvres, moreover unlike Canada the US has virtually unlimited funds for aircraft support and maintenance; if they wanted to I've no doubt they could trot out a fleet of model A cars with wings and make them fly successfully. The B-52 is a robust plane maintained by the best funded military establishment on the planet; which additionally has had far fewer demands put upon it in the last thirty years since the introduction of the B-1 and B-2 bombers starting in the 1980's.
The USAF spends more on maintaining and servicing their bomber fleet alone than we spend on our entire armed forces annually therefore I would expect all of the aircraft in their inventory to be in top condition. And besides as any good accountant will tell you the costs of maintaining depreciating assets, older aircraft in this case, skyrocket exponentially as the aircraft ages.