Perhaps you assume too much. Obviously, if I can afford to hunt Africa four times and counting, I could afford a double rifle. Your assumption is everyone who can afford one should be inherently biased towards hunting with one. That is the definition of stereotype. Variation is what made us an evolutionary success. Why would anyone choose now to fit a stereotype? Every dandelion weed is different. Different from every other dandelion plant anywhere that is and ever was and ever will be. Differences in size, shape, flower structure, root structure, cell structure. Why would a human being at the very pinnacle of world evolution choose NOT to find his/her own distinct path through the one and only life he/she will ever have?
I wasn't talking about you. I was talking about the professional hunter. The stereotype of the professional hunter (delighted for the exceptions) is their nearly unusable rifle is the best rifle, when in fact it was the free rifle they got lent or gifted out of pity as an apprentice. Occasionally clients will have the same reaction, trying to justify the incorrect tool for the job at hand out of pride, naivety, or obstinance.
If Harry hadn't had his deal-of-the-century 470NE run over by a truck, he'd have stuck with it. Had Kerr found him a replacement 470NE like he requested, he'd have owned that. Had Kerr found him a magnum action 416 Rigby he would have definitely taken that. In the end, they found Harry Selby a cut-rate 416 Rigby that was too cheap for good reasons and Harry made a career out of using a reliable gun that was less than desirable because "Beggars can't be choosers".