Deliberate mistake: After Baloo and Bagheera escape from the monkeys, they both have a black eye. However, during their conversation by the water, between shots their black eyes vanish. [This is a Disney tradition, but still a mistake.]
Deliberate mistake: When Baloo lies unconscious, the tree behind has barely no leaves on its branches. When he wakes up and the sun shines, leaves suddenly appear.
Answer: The animals considered man a strange creature and did not understand their ways, like wearing clothes and shoes. They were scared when Mowgli brought them fire. They only knew jungle ways, they figured the humans would eat him, like any small creature left on his own. Plus they knew man as a hunter and killer.