This is rather a style, not a common mistake. We should maintain the same pattern in a list or series so that it creates a vocal harmony as we read through the whole sentence.
I love fishing, skiing and to climb rocks.
I love fishing, skiing, and rock-climbing.
The cake was baked, frost, and sprinkled.
The cake was baked, frosted, and sprinkled.
Sharks are large, damp, and dangerous.
Sharks are large, damp, and not to be trifled with.