Remember your O.A.C.I
Offer
Acceptance
Consideration (aka. payment)
Intention to enter into legally binding relations.
As long as any of these elements are not fufilled, they have no power over you and you can tell them to buzz off.
As in your case, you never even gotten past the offer element, hence they cannot force you to do anything. The only thing really keeping you there is because they made you think that you were obliged to stay and listen to them when in actual fact, legally, there is nothing they can do to stop you from refusing and walking out and as a matter of fact, their actions are not exactly legal and could get them blacklisted. Remember that you were only obliged to pay your consideration for the facial and nothing else. Anything else is entirely up to you.
Often some hecklers try to take advantage of the consumer's ignorance of the law of contracts to force consumers to enter into legally binding contracts when from the start, next time, just raise one arm like the Rock, refer to yourself in the third person and say:
"You know what the *insert your name here* thinks? IT DOSEN'T MATTER JABONI!" and walk out.
