Popcorn — the kind you buy in bulk and make yourself — is a very economical snack. Less than 40¢ per serving (and I mean a man-sized serving) for the popcorn kernels and quality popping oil.
But to do it right, you need a good stove-top popcorn popper. I have a popcorn popper like the one in the picture. Stainless steel, with a very study handle to turn the paddles that move the kernels. (And note that the handle is directly connected to the paddles, no gears to wear out and break.) It cost about $80, but it’s a piece of quality cookware.
Over the past few decades I’ve had at least 3 or 4 popcorn poppers: the hot-air popper, the motorized electric popper, some microwave contraption, and probably some other thing. Nothing tastes as good as popcorn made on top of the stove. Anything electric will eventually break. Plastic is junk. There’s no need to pay for something that uses electricity to make heat when you already have a stove.
This stainless steel popper will probably still be in working order decades from now. Despite its relatively high cost, it saves money because it will last longer than other poppers and it makes popcorn that tastes better and costs less than microwave popcorn (and much, much less than bagged popcorn or potato chips).