Just because a guy is cheap doesn't men he shouldn't enjoy the finer things in life. I happen to have an affinity for single malt scotch. That means I have to shell out at least $40 and often $75 or more for a bottle of decent scotch. Sometimes embarrassingly more. But, being a cheap guy, I make sure I get my money's worth. I check the levels before I pick a bottle.
You'd be surprised how much variation there is in the fill level of a booze bottle. Sure, if you're talking about mega-corp giant distillers, every bottle is depressingly the same. But boutique bottlers, like the distilleries that make fine single malt scotch or local premium hootch like Tito's or Dripping Spring vodka here in Austin, aren't that consistent. Fill levels between bottles can vary by as much as a full shot.
One 750ml bottle of scotch is good for 15 shots. At $75/bottle that figures out to $5 a pop. So do yourself a favor. The next time you're buying a bottle of boutique booze, pick the one that's the fullest and you might get 16 shots. Why not buy yourself a $5 drink?