Seedy little plants

I went outside today and looked over the front garden and saw tiny little plants growing in the gravel walkway. I knew there were some weeds creeping in and trying to make it a weed bed but I was a little surprised to find some other plants sprouting up there. Mainly, besides the weeds, there was cilantro. I really like cilantro, as long as there's not too much of it at a time, but now there are dozens of little plants along the edge of the gravel and I'm afraid I will have to uproot them and toss them to the side like the rest of the plants. They have journeyed to the realm of weeds since, as we all know, weeds are merely plants that are growing where you don't want them to.
Another newcomer to the weed family, in my case the plants that are growing in my gravel walkway, is fennel. There are only two fennel plants sprouting where they shouldn't but that's still too many. It's hard enough to keep the grass out.
I wouldn't have this problem if they weren't so reproductive. Both plants produce many seeds every year and have no problem dropping them where they shouldn't. Ok, so it's partly my fault for trying to harvest some of the seeds for cooking but I don't want to complain about myself...