I don't believe it... a conference that I'm submitting to has an EULA. I thought that for once I would read it. It contains such gems as:
I acknowledge I have read the above information and that I am 18 years or older.
I understand that my participation is voluntary and that I can withdraw at any time without explanation or penalty.
... which seems a bit harsh if I was a prodigy trying to submit a paper to the confernce. And if I choose to withdraw I will suffer a penalty: my paper won't get reviewed. It's all very, very silly.