I cannot speak for all flights or geographic areas but I get a lot of clearances to cross 30 miles from my destination airport at 11,000. Typically the airport in question is around 1000 feet elevation so I need to lose 10,000 feet in 30 miles which means a serious power reduction to keep the speed and the rate of descent down, or a dive at about 180 knots and 1000 FPM. Neither is a good option because the first is hard on the engine, and the second option is just not an option if I encounter any clouds or bumps. I am way above a safe speed for turbulence.
I explain I have animals on board and even though I am pressurized me and the animals like a slow easy descent and having our own call sign signals to the controllers we have tender ears on board. The most important reason however is that other pilots will hear the call sign and start thinking about volunteering, and we really need more pilots.