This is not intentional. Its how genes work. The seed on a plant depends on the pollinator. Just like fruit trees - you plant that seed from the apple you just ate, it won't grow more of those apples. It will grow whatever that apple was pollinated with.

This is true for many flowers and garden crops, it is not true for corn, soybeans, & similar.

The viability of hybrid offspring depends on the closeness of the parents. Lots of flowers can be bread from very diverse stock and the offspring are sterile, cash crop hybrids are not made from such diversity and are generally re-plantable.

Corn is generally carefully crossed as a last step in hybridization. The next generation will grow a plant almost completely dissimilar from the one being sold.

Its an issue trying to support farmers in developing countries. Our Romanian sister church didn't accept our corn hybrids. They had their own 'land race' seed they've been creating for generations, which works well on their difficult soil. If we sent them hybrids, they'd work for one season. And then they would be dependent on us for continuous shipments of seed each spring. We left them with their self-sufficient seed.