Let's say a hotel chain or a restaurant provides a 50% discount to anyone aged over 70. Would it be legal (as in, no criminal charges could arise from that action) for a patron to lie to the hotel/restaurant about their age to get the discount?
Question is restricted to US law.
It is basically fraud, and there are two ways in which it could be illegal: it might be a crime, and you might get sued for doing it (you would not be fined or imprisoned, but you may have to compensate the hotel chain for their loss). Whether or not it is a crime depends on the jurisdiction. In Washington, there are very many laws against fraud such as RCW 9.38 (credit), RCW 9.45 (numerous things where a business defrauds others), RCW 9.60 (forgery) but none of them would apply to lying about a material fact to a business in order to get a discount. Texas likewise has a long section on criminal fraud. It is not clear from the wording whether a customer lying to a business (not involving forgery, vehicles, credit, or financial institutions) is covered. 32.42(b)(10) says
A person commits an offense if in the course of business he intentionally, knowingly, recklessly, or with criminal negligence commits one or more of the following deceptive business practices... making a materially false or misleading statement of fact concerning the reason for, existence of, or amount of a price or price reduction
The question of interpretation that this raises is whether a person who has said "I'm over 70" so that they can get a discount has made a statement "concerning the reason for a price reduction". The ordinary interpretation of "concerning the reason for" would be that it refers to explaining why or under what conditions a price reduction exists. For the moment, I am skeptical that this definition would include the case at hand, but that will require a search through case law and jury instructions.
From the lawsuit angle, you would have knowingly made a false material statement in order to obtain a value, which is illegal, and they could sue you to recover the discount.
If the business is charging you less than they would have if you'd told the truth, then they are losing money because you lied to them. You are obtaining something of value at the business's expense under false pretenses, and thus are committing fraud. It's difficult to find a specific criminal statute violated, because most of these cases are civil matters. But in Virginia for example, a liberal reading of ยง18.2-188 may apply.
...
It shall be unlawful for any person, with intent to cheat or defraud, to obtain credit at a hotel, motel, campground, boardinghouse, restaurant, eating house or amusement park for food, entertainment or accommodation through any misrepresentation or false statement.
Unless you've racked up $thousands in discounts, the chance of criminal charges is pretty low, but nonzero. Either way, misrepresentation is grounds for terminating the contract allowing you to stay, eat, or whatever. At the very least, you may get a very unfriendly wake-up call and/or some help leaving the establishment. :P
(All this is assuming you succeed, of course. If they don't buy it, then you might be better off.)
Aside from that, the business didn't just take your word for it that you're 70, because it knew some schmuck would lie about their age to get half off. So you almost certainly had to present an ID. If the ID is fake, that is often a crime in itself.
Fraud must be proved by showing that the defendant's actions involved five separate elements: (1) a false statement of a material fact,(2) knowledge on the part of the defendant that the statement is untrue, (3) intent on the part of the defendant to deceive the alleged victim, (4) justifiable reliance by the alleged victim on the statement, and (5) injury to the alleged victim as a result.
https://legal-dictionary.thefreedictionary.com/fraud
So if you claim to be over 70 when you're not, that's a false statement. Presumably, you know it's false, and the very fact of claiming it shows an intent to deceive. Where things get fuzzy is "material fact", "justifiable reliance", and "injury". If the hotel's discount doesn't bring the price below their marginal cost for the room, then arguably they are not harmed. One could counter that they are being harmed in that they could have gotten more, but that is stretching the meaning of "harm", and the defendant could argue that were it not for the discount, they would have gone to another hotel and the hotel would have gotten nothing.
As for a lawsuit, simply filing the case will probably cost more than the discount, let alone legal fees.
So, all in all, while you theoretically could be charged and/or sued, and there are arguments that would support a conviction, in reality it would be rather unlikely to face such consequences, and you would have viable defenses if you were.
