how do you deal with long distance events?

CHARGE ACCORDINLY     for yours and your employees both ways.and time   gas is not cheap, nor is your time.

That's a long drive after a long day.  My answer would be to stay in a motel, but I haven't met a client  yet that would spring for that!

You don't tell a client that, you just figure it in your estimate to them.

Logistics, your costs are higher than some one who is closer to the event. I remember you doing a function a few years ago that was a distance from your home base..........................some times it just cost more to get the best.................ChefBillyB

Charter buses do work; I done a few caterings with this type of transportation.  There are usually local temp staff services but unless you know or have worked with them before it can be tricky.  The ride home is always a good time if you have a tight staff and a designated driver

This kind of goes along with a question I have for my very small catering business. My family has a restaurant and my wife and I run the catering side of the business, mostly weddings and small functions. Would a "Travel Fee" for jobs more than 25 miles away be acceptable? I hate having to charge the customer fees, but so far I've found it the easiest way for jobs that are more complicated than others and have had only a few complaints (from people that I wasn't sure I wanted as clients anyway, lol).

With the price of gas almost all wholesale deliveries now add a surcharge, so why shouldnt you . You can either add it at end of bill, but tell them up front. Or you can add lets say 50 cents pp on 100 people and build it into price.  Your choice.