Two kids I know were walk on situations. One was a late bloomer who had a great senior year. Two coaches told him there weren't any scholarships left. They also told him he would have to get accepted to the college without help from the baseball program. They both promised a roster spot if he was accepted. He's now a junior pitcher at the college he got accepted.
The other was told nothing but he could attempt to walk on. When tryouts were held the head coach wasn't there. After less than an hour the assistants called the players in to tell them they wouldn't be taking any walk ons from the tryout. Talk about dishonesty from the head coach. He knew all along.