Hybrid seed is common. It is not necessarily GMO. In fact, most hybrids are not GMO. But saving hybrid seed might be disappointing. The seed will not breed true. What you get from a hybrid is a crap shoot. And this is important to know about hybrids if you like to save seed. Sometimes you might get something that is just fine. In fact, some gardeners have started with a hybrid and grew it repeatedly, stabilizing the seed into a new variety that is open pollinated. But more often than not, the plants from seed saved from a hybrid are disappointing. Or worse yet, the hybrid has sterile pollen, making seed production impossible unless you bring in outside pollen from another variety.
The only hybrid seed I intentionally saved was from a grape tomato and a small pumpkin. . After a few years I stabilized a grape tomato that does good on my farm. So I ended up creating my own landrace open pollinated grape tomato (actually tomatoes are self pollinators). The pumpkin I don't bother to control, so I get a lot of variation every generation that I grow it. The only trait I select for happens naturally --- the ability to produce pumpkins in the presence of pickle worm moths that visit my farm.
Hybrids usually have the advantage of desirable traits. They might have sturdier plants, shorter vines, earlier harvest, better disease resistance, or produce more food. They usually are more uniform than their open pollinated cousins. Thus for example, all the broccoli heads are about the same size, shape, and are ready the same week or two. Hybrids often have better disease resistance, and in Hawaii that can make the difference between harvesting a crop or getting zero.
Do I grow hybrids? Yes. I grow a hybrid broccoli called Green Magic because it will produce on my farm even when the weather isn't right. There are several hybrid cucumbers that do better for me. There was a hybrid cauliflower I adored but it's no longer around, called Violet Queen. I wish I knew what it's parents were. I'll grow some of the hybrid carrots, since I don't save my own carrot seed. And some specialty sweet peppers and tomatoes, because they produce better. And some hybrid tomatoes because I like to experiment. I have no objections to growing hybrids. I just don't try to save seed from them.