Is it unethical for a computer maker not to include the gerbers for the mother board and the masks for the chips when they sell you a system?Why make analogies to completely unrelated things? Tell me which is within the user's means to modify or pay others to modify: a piece of software or a hardware ASIC. Tell me which one is naturally predisposed to making infinite copies with no generation loss at zero marginal cost. Tell me which one is restricted from duplication solely by artificial government intervention.
Are you seriously inferring that software is not a special case? Is it not different from physical materials which perform a fixed function, and printed works which describe something, while yet encompassing properties of both?
It is not so simple, and blithe analogies do little to underscore your position. I sympathize with your position though, as we all need profit to survive. Luckily, I am able to work in an area (web development) where I can hand the keys to the customer and it doesn't affect my chances of landing another job, as long as we have managed to please the customer.
Licensing the source code to your customers under the GPL isn't as damaging as you might think. Most companies would not even dream of giving away the custom application that they paid to have developed, to a competitor in their line of business. At worst they might sell it to a competitor, but are they equipped to develop and support it the same way you are? Experience has shown that this back-stabbing by business customers is rarely an issue. For consumer software, it might be quite a different case, because there is a strong incentive for sharing among friends.
RMS would have a better time convincing people of his position if he would work towards providing models under which people can write this "ethical" free software, and feed and clothe themselves and their families as well.
Maybe one idea would be to sell a proprietary package with the guarantee that at the time when support ceases or the product is no longer for sale, the software will be freed. Or say that once X units have been sold, it will be freed. Buyers who have the money will have an incentive to pay (because they don't get the software until after X people have paid), and in the long run, the users aren't stuck with an unmodifiable, non-redistributable, non-working piece of software that they paid good money for.