The short answer is you might need it, so it doesn't hurt to have copies available.
However, having copies of your resume in your bag does not give you permission to hand them out freely to anyone near you at the event. Instead, when you talk with a representative of a program, it is much better to exchange business cards and then have an intelligent discussion about how their program can help you to achieve your academic or career goals.
I get concerned sometimes when people mention how essential it is that they "hand out" their resume at the MBA Tour. It is easy to picture them avoiding a conversation, avoiding asking good questions, and therefore avoid saying something positive and memorable about themselves, all while they instead hide behind that piece of paper. I've seen it happen more than once before, and no matter how good the resume may appear, the impact is not as strong as inquiring about their school, and managing a quick and effective conversation. Don't forget, there are other ways to continue the conversation. Once business cards are exchanged, it is common to follow up a day or two after the event with a polite email, thanking them for their time, and even recalling the conversation or asking a further question if you feel it warranted.
So do bring copies of your resume in your bag, and have them ready in case anyone asks you for a copy of it. But don't let the resume act as a replacement for a conversation.