i used to take vitamins and B12 pills, but i've been told mulivitamins are bullshit so idk.
did this person tell you that multivitamins were bullshit, or just vitamins all together? multivitamins are ultimately kinda crappy when it comes right down to it, but that's really only in comparison to specific nutritional supplements, which seem to have a more observable physical effect when taken. vitamins and supplements are extraordinarily useful if you just aren't able to get everything you need from your diet. from the way you characterize your current lifestyle, it doesn't sound like you probably have a particular need for any of that, i'm just saying.
actually i mention this because it may have been me that told you that multivitamins are bullshit, and they aren't if you don't have the means/interest/time/whatever to thoroughly research nutrition and go out and buy 25 bottles of vitamins and shit.