Why not ? Or is that a stupid question. I have loads of blackberries in the garden and I got some new ones by pegging a trailer in a plant pot until it rooted then cutting off the stem to the main plant. I was just curious if you could just plant the fruit and wait
Blackberries multiply by sending roots down from their stems where they touch the ground All plants have developed their own methhod of multiplying eg oak trees from acorns, strawberries send out suckers which develop into small plants. The bulbs of daffodils seperate into lots of bulbs because growning from seed takes years.
It is possible to get new plants from seed but they are double dormant so need a lot os specialist treatment to get them to germinate. You would not just be able to plant the berry and expect to get seedlings.