I was called for U.S. District Court once. You have to be on call for a variety of cases that may come up; so if you are not picked for a jury, you have to stick around in case something else comes up. I spent one whole day in the pool of available jurors, and was given a # to call to see when we were meeting again. Fortunately, I was not needed after that one wasted day.
You could always do what a lot of people do - pretend you never received the summons.
Where I live, there's supposedly a $1,600 fine for ignoring a jury summons.
I chose Christmas time as my postponement. Was picked to go to a courtroom, but the judge came out and said they weren’t ready to go to trial yet and sent us all home.