Is it possible to get a judge to marry people at a restaurant?

Call City Hall and ask who is allowed to marry people in your area.

If a judge won't do it outside of a courtroom, then look around for a professional wedding officiant for hire, or maybe a non-denominational religious minister who will inappropriate as much or as little religion as you'd like into the ceremony. Or get a friend ordained online, if your state allows this, and write a ceremony with them.

A civil celebrant does not need to be a judge. As long as (s)he is properly certified by the state, you can use anyone you'd like.

Maybe not a judge.

Who could legally marry you?

Google Justice of peace where you want to get married.

Some people who go by Rev, will do civil ceremony.

They may be ordained.

If you get a list of people that will marry you where you want, you may find some that will do an civil ceremony in an restaurant.

I been to one, but the judge was a friend of the groom

You would have to ask a judge for a personal favor. They make plenty of money on their own and do not likely have much desire to do weddings on the weekend, or are equipped to handle the paperwork. Just hire an officiant like everyone else.

You might look into finding a retired judge, they are still authorized to perform weddings.

Yes