Yes, the official SmartThings widgets are only associated with routines.
If you are in the US, you have some additional third-party options.
You can use IFTTT do buttons. This is a free service.
If you have iOS, you can buy a $9 third-party app called smartrules which is both a rules engine and has widgets. I like this one a lot.
If you have android, you can buy a third-party app called sharptools. Not a rules engine, but does have widgets. Also very nice.
@joshua_lyon
The following FAQ covers some of the scheduling options in SmartThings. It might help: