The corporate visionary shared his dream that one day Americans could go into McDonald's and order food specially engineered for their health needs. If human genes were successfully introduced into plants, their transgenic pollen could contaminate neighboring fields. Unlike cars with exploding gas tanks, genetic alterations cannot be recalled. Human genes introduced into potatoes or any other crop could become a permanent part of that species. Genes are just molecules.
Human genes are no different from other genes.
Variants of the reductionist view are so pervasive that many environmentalists fall prey to them. The last thing the food industry wants is a national debate which suggests that society itself should determine uses of biotechnology. They see no reason to discuss what should or should not be put in food because they intend to put anything in food which is technically feasible and economically profitable. To them profit equals morality and everything else is a nuisance factor to be handled by a PR department. When a tomato with a flounder gene was introduced, the fact that consumers would not know that it had an animal gene was not treated as a problem.