At a wedding expo, there are endless vendors who offer services ranging from wedding limousine hire to food catering and invitations. When I was a bride, I never went to one. I lived in Wales at that time. For the most part I was finishing my final year of university. In the holidays, the groom had found three places on his own for us to look at. We went to a local party/print shop to pick out invitations. They could also have designs printed on napkins.
Back in Wales, I worked on making my own dress. Everyone was a bit dubious if I could achieve such a feat since I had little experience in dress making. I had never made anything except for a knitted top as a class project in primary school! I was inspired by another girl who threw together a dress for a university dance. She claimed you could do it with "sticky tape and glue." At one point she put it out in a small cement court yard so she could spray paint it! It was completely haphazard but she was just having a go. When she finally showed up at the university ball, I was amazed! She gave me the confidence to have a go at doing it myself. I reasoned - if she could do that, I could do that too!
I never even thought about hiring a car for the wedding. I never thought to ask for a limousine when my parents offered to hire a car. They actually called an airport car transfer company. It was basically a simple town car. I would have happily stuck myself in the back of a small run -down car that belonged to a friend and bridesmaid, without a clue! Neither did we hire a getaway car. The wedding and reception were in the same place and we drove off to another state in our own car which the groomsmen decorated.
Looking back at my ignorance, I would have to say that a wedding expo can help so that even if you do not use any of the services offered at a particular expo, you know what is available. You might find some really great vendors and can book their services in advance for your special day. Or if you are a D.I.Y. type, you can get some fuel for your creativity - even dress making.