Normally we say 公園を散歩する because 散歩する is a verb that expresses movement in space, and is thus followed by を, which also expresses movement in space.
But if the verb is changed into 犬を散歩させる, in this situation, why is で added to 公園, rather than を? As I often see expressions like: 公園内で犬の散歩をすることは禁止していません.
I think both 犬の散歩をする/犬を散歩させる and 散歩する express movement in space, then why don't we use 公園を in the condition of 犬の散歩をする/犬を散歩させる?
If it's okay to use 公園を犬の散歩をする/犬を散歩させる,then why do so many people choose to say 公園で? What are the differences between them? I would really appreciate it if you could give me a detailed answer of this problem!!!