Not sure that's 100% true. Many winter tires are really just designed to remain flexible in cold temperatures, basically to work similar to a summer tire in the temp ranges of a summer tire that turns into a rock in the winter. Look at something like the Micehlin Pilot Alpin, Pirelli Sottozero, etc. These are performance snow tires. They're mostly made for the reasons above. They may get you through light stuff, but they're not a snow-slaying tire. Even the Xice 3 which I have has higher speed ratings than something like a Blizzak, a true snow tire. For our area where the snow is plowed constantly, the Xice and similar is what I would go with. Unless you live in Vermont, a Blizzak or other true, deep tread snow tire is overkill.
for true snow tires it is definitely true (per one of Michelin's own engineers) the tires that 'get you through the lite stuff' are classified as all seasons (per the same person, this may be an internal classification, not a marketing one, im really not sure) with some varying degree of snow rating. If you ran one of those tires in the summer the only negative impact would be wearing them out faster (you also give up the high performance grip that a dedicated summer tire gives you).
My wife drives a genesis coupe (hyundais so called performance coupe) all year round with a set of standard all season tires on it with no problems for the last 7 years.
I would never recommend driving a summer tire through the winter for exactly the reasons you stated above, but then id also tell 90% of people to buy the less expensive all season tires for their cars since they dont get driven beyond the limits of that tire so they dont need the extra grip offered by a performance tire. . . .