They gave you good advice, firstly they stand to get your money, secondly they take no risks - you take them all! But, you can be assured that probably the worst thing that will happen to you if you are caught is that you will be deported from the USA and will be barred from re-entering again if that's a risk you are prepared to take! You can be caught very easily if you are involved in any sort of "incident" or get ramp checked.
I would also be interested in the school that gave the advice and so no doubt would the US Immigration and Naturalisation Service. Who was it? post it here and I promise not to tell a soul!
