Coins that the services will grade cameo are very few and far between butit's true that many of the SMS coins have at least lightly cameo. A full quarter of something like '67 quarters have at least a light cameo but it's much lower for '65 and '66 issues and for cents of all dates. Many of these lightly cameo'ed coins are really quite stunning but they have been selectively removed from sets over the years making them seem far scarcer than they are.
But heavy cameo coins with even cameo on both sides and with basined surfaces and cameo cents are very elusive.
Time don't fly, it bounds and leaps.