Should you always compare the price?

When you are promoting your business, should you always tell people what you can buy for the same amount of money, as from joining your business? I think that you might want to do that, especially if the price is not too high. For instance, I have just received information about a product that cost $7 (a one time fee). In the sales letter it says something like, would you rather buy a medium sliced pizza ($9.95)? This puts the offer in perspective, what can you get for the same price? Some tell you the price per day. For instance if the business costs $29.95 a month, they say that for only $.99 a day you can join a great business opportunity. This makes it sound so much cheaper than the $29.95 a month, doesn`t it? Anyway, I think it might be something to consider. Use the price and compare it to something else, like the pizza example above or the price to watch a movie or something people can relate to. If you do this, the actual price of becoming a member of your business might not sound that high.