It is often said that too much of everything is not good, I think that applies to fear too. To fear is not actually bad, but when it is getting out of hand it can actually be destructive.
Like you said, fear at times could help us be on guard not to wrong God. But destructive fear is actually a tool Satan uses to lure people away from God. Fear of disobeying God today makes some people refuse dedicating their lives to God.
This is a very good topic you brought up, I'll like to see the opinions of others on it.