I'm not a pro shop guy, but I think I can answer the first two questions.
Because the customer is always right. I've seen it happen plenty of times, THB comes in, asks for latest hooking ball.
THB: I want HOOK MONSTER
Pro Shop: Ya know, I really think this medium ball would be better
THB: Nope, I want HOOK MONSTER
If the pro shop guy doesn't sell it, THB will just go down the street to the other pro shop that will.
As far as the bowlers go...well, I don't know. If you figure it out, let me know. A couple weeks ago, a guy on my team asked me about a new ball. I gave him 3-4 choices. All were medium/pearls. A guy that works in the pro shop was throwing a Jigsaw Corner that nite and my team mate asked me about it. I said it was too aggressive for what he wanted. The pro shop guy said it was too aggressive for what he wanted. Well the pro shop proceeded to shoot 700 (Because he's freakin good) so of course my team mate had to go out and by a Jigsaw Corner. Next week he barely broke 500 (He averages 208). I've stopped trying with some people, they refuse to understand that a bowling ball only has so much energy, and sometimes, the reason it's not hooking isn't because they need a stronger ball, but because the ball is too strong and is burned up by 20 feet.
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It IS next year!