This leads us to so called "free will". Like free markets (or free lunch for that matter) some people believe in it with religious intensity, and just like with free markets, where ever we look we don't see anything even approaching 100% free will that prevails in life.
Sure people say that want something, but it seems this is largely because they have been told by family and friends that they should want it. For example, in theory children should have different careers than their parents, and the great promise of education is to elevate people out of poverty and low wage jobs. Yet studies find that, contrary to the rosy optimism, most kids don't do better than their parents. Most kids go into the same or very similar professions as their parents. There's this myth about upward mobility, which supposedly comes about due to higher levels of education, and it is cherished one, particularly in America. While it may be true for a few people, they appear to be the exception, rather than the general rule.
Consider, as well, the people to whom we are attracted or marry. While some diehard religious types like to insist that homosexual attraction is a "choice", heterosexual attraction appears to be fairly clearly dictated by hormones and a variety of built-in biological preferences. People end up being attracted to other mates that look similar to them, and hold similar opinions, and come from the same socio-economic background. Again, there are endless fairy tales about rich guys marrying working class women, but it doesn't usually happen, movies notwithstanding. As above, we even marry people who are similar to our parents.
Whole fields of industrial psychology explore how to get people to spend more money or make purchases that they would not normally make. Real estate agents, for example, find that when a house is "staged" with furniture and decorations, for example, that they tend to get a higher price for it than when it is sold empty. Adjusting the temperature in a bar, or the kind of music in a restaurant can cause people to spend more money without even being aware that they are doing it. It is not 100% cause and effect, but it increases the odds a noticeable number of percentage points, on average.
Think of free will like the flip of a fair coin. It is free to come up heads or tails with equal likelihood. However, if we start monkeying with the coin so it becomes 45-55 or 40-60 or 30-70 odds then we now have some seriously rigged choices. Purists will still say that you have the same two choices or heads or tails, but you're being pushed by forces outside of your own will to make certain choices, often without even being aware of being influenced. There is really some thing or even some one who controlling the probability that you will make a given choice. If you still want to call this a "free choice" then that's because you were programmed to say that ;-) Seriously, though, it's not what most people would call free choice.
Please note as well that I am not talking about mere physical limitations on what it is impossible to do. The traditional example is that one has "free will" to flap one's arms like wings, but the physical world makes it impossible for you fly like a bird by doing so. I am saying that even the desire to choose to flap your arms like wings is subject to interference and manipulation by external forces. In theory, people have a wide range of choices in any given situation, however, in reality, only a very limited selection of choices get made. People can't very well choose things of which they not even aware exist. By constraining peoples knowledge of the possible choices that exist out there their "degrees of freedom" become more limited.