>>As a dealer, he could easily factory-order 18hp models with the 25hp props (no price difference), and as many 25hp restrictor plates as he wanted (at just a few bucks each). No-one cared about the 18hp decals so he didn't bother ordering the 25hp decal kits.
>>
>>So, us guides got the nicer motors we wanted, and the owner got the cheap price he wanted.
>>
>>The moral to the story is not to make artificial market distinctions; it's just a license to lose money.
>
>Not sure - yiu still get the "stupid" money (minus some dollars for more marketing and diferent parts...)
>with the 18HP price as baseline...

What happens in practice is that tooling for motors is expensive and OB volumes are not that high, so builders limit the number of mechanically different models they produce. Then they resort to dumb tricks to make their product line look wider.

They could reduce complication and offer lower prices if they said "we only offer a 25hp model, not an 18 as well".

There used to be regulations that certain boats/operator ages (think children) were limited to 10hp or less, hence the proliferation of so-called "9.9" motors. But, that market is/was large enough to justify models optimized for that power.