Ideally, you would not consume these at all. Sure, go ahead, you say we're lecturing you, but that is the defacto truth.
A multivitamin is cheap insurance (assuming it's not a megadose vitamin - one where there are many over 500% of the RDA, etc.), but it is also unnecessary for someone eating a balanced diet (I haven't taken vitamins in well over seven or eight years now). And unlike what previous posters have suggested, multivitamin supplements are generally designed for maximum bioavailability - sometimes even more than found in foods, which is why abuse of supplements can lead to overdose (such as with nutrients like iron, vitamin D, etc.
If anything, these products are more worthless. They take "extracts" of fruits and vegetables, throw them into a pill, and expect consumers to believe that it's the same thing, which it isn't. Moreover, there is too little amount of anything to do very much at all, in my opinion. Moreover, the research just isn't there to support the efficacy of supplementation vs. the real thing. If you want to waste your money, go ahead, but don't fool yourself into thinking that this is replacing 5-8 servings (I personally think it should be 8-11 servings) of vegetables and fruits (in that order) a day. Americans are far too obsessed with focusing on single nutrients or compounds in foods and then packaging them into pills to take, rather than just taking the easy route - eat the food. A whole lot of energy, time, and money wasted.
Whole vegetables have far more physiological benefits than just the macro-micronutrients they contain. They help reduce calories, contribute to satiety, bind carcinogenic substances in the small intestine, blunt insulin response, aid with GI function, contain phytochemicals (which we really still have limited understanding of), and a host of other health benefits.
Why don't you eat any V&F?