Motorola is not loosing money on this. They have accounting numbers that tell them that having a modifiable device ups their support cost. People without the real technical ability or (worse) people with no technical ability that have friends/relatives who do the 'upgrade' for them cost money in support. The difference in manufacturing cost over the production run is insignificant (i.e. they are not increasing the end-user cost based on this change).
Companies like Motorola know most of their customers are apathetic to the needs of hackers and look to the bottom line. Apps will still run on the phone, so customers will still have that. This is a win for Motorola in the market they serve.
I'd be interested to see some proof that this is why this is happening.
The best reasons I've read for why Apple is so hard on jailbreaking is (a) carrier agreements not liking unlocks and (b) pirating of apps. I find these reasons a bit more compelling, although like I said I'd like to see more information about it.
Companies like Motorola know most of their customers are apathetic to the needs of hackers and look to the bottom line. Apps will still run on the phone, so customers will still have that. This is a win for Motorola in the market they serve.