I've been thinking a lot about how enjoyment and delight are really quite distinct from reward (in the Skinnerian sense). I think plenty of other people have gathered insight adjacent to this. Jocko Willink's 'Discipline is Freedom' points to clearing out reward specifically to help choose to spend effort on things you value – and that it's distinctly not the default path. From a different angle – and from the opposite end of the philosophical spectrum – 'dance like nobody's watching' is about cultivating delight in the face of strongly anti-rewarded behavior. I guess this is my slight addition: pay very close attention to enjoyment and reward.
You could spend your entire life doing things you don't enjoy, value, or even care about, because it was rewarding your inner pidgeon! This seems like the modal outcome for reasonably well-off people.
I was once very skeptical of the idea someone could classically condition themselves with something as simple as a bag of M&Ms they use as a small incremental reward. As has been pointed out, if that worked the naive way people suggest, it would classically condition you to just eat the M&Ms without doing whatever task you're trying to reward yourself for (because 'grab an M&M' is both lower energy and more directly tied to the reward of 'eat an M&M'). If you haven't conditioned yourself to walk downstairs for a snack, then it won't work...
...but of course many people have in fact done this. The obesity epidemic probably has a lot of causes – maybe plants build more structure in the presence of ~double atmospheric CO2, maybe it's microplastics, maybe it's just food getting more delicious so for constant benefits to health the equilibrium weights have gone up (as we'd expect for higher opportunity costs of missing out on more delicious food). But a serious contender for a major cause of obesity is that we've managed to make extremely high reward foods. And I'm not even sure we really even like them all that much. I mean, I've had amazing food, and I'm less likely to overeat that.
It's also worth saying life isn't all about enjoying things. Lots of non-enjoyable stuff is pretty important. But... you should enjoy some things, and those are the ones I see most often crowded out. I have only the barest wisps of wisdom here, so I'm not sure what to do once you notice these distinctions. But if you see a high-reward behavior you don't value... seriously consider making it a priority to change (and maybe change to something you do value – going from candy to broccoli is a recipe for failure in almost all cases).