Because THAT, at least, generally won't be taken away or lost due to hardship or anything of the sort...
Unless I'm DEAD, I'll probably be able to get some carrots, noodles, and water.
It's realistic.
Besides which, when you eat, you start with a surplus and end with a deficit...I just don't get the fun in eating something when you don't have to, really, unless it's the most amazing occasion ever...taste is pretty irrelevant to me to a large degree--I had a mostly taste-free diet growing up--and in any case, that's what tea and drinks are for..and THOSE are less expensive, and are more economical--
You eat something, it stays with you, if you want more you have to order more, and once it's gone, that's it, so if you liked it...well, there goes whatever made you happy.
You drink, and you can get that refilled, or buy some more pretty cheap, and it's renewable, so you don't have to worry about running short generally...and you just piss it out every now and then and you're on your way, no extra hassle during the day.
Whatever, I'm probably wrong--my friends all agree it's odd as well, so it's not as if this is an English vs. Math debate, I'm pretty much by myself in this regard--but that's just the way I'm programmed and function...and it's never failed me yet to get me through a semester, I don't pass out or anything...
And it's always nice to know, from my point of view, anyway, that if there's nothing to eat or I'm too busy to eat, I'm not going to feel horrible because of it.
Maybe everyone else feels better due to the endorphines and all, but, again, it's like a girlfriend in that regard:
I'd rather have a stable, dependable "relationship" with a friend/water and know it'll be there for me when I need it, than risk getting sick or whatever eating the wrong thing or losing a friend in a fight over whatever...
I'd also mention--
No sex and minimal food expenditures=FAR more time to read, write, and think about things, which I enjoy...
So three pleasures vs. two...