Being a sports fan is great, simply because someone is always trying to sell you something. And companies have been doing it since the beginning of sport. Two of my favorite product tie-ins are the Salada Tea coins from the early Sixties, and the lapel pins made by Sweet Caporal cigarettes in the early Teens. I think I like them so much because they fit a few of my criteria: 1) they're comparatively cheap and 2) they're relatively easy to find, and 3) they're listed in the Standard Catalog, so there is a complete checklist known for each set.
Additionally from a historical standpoint, both sets are accurate reflections of the stars of the league at that particular time. Today, nobody under the age of forty can tell you who Norm Siebern was, or why he warranted his own coin, but once you handle the coin, take a look at his stats and look at the KC emblazoned on his cap, you have to guess that this good a hitter had to have something to do with the New York Yankees, as the KC Athletics were basically a farm team for New York, the way they dealt with each other (much like the Minnesota Timberwolves and the Boston Celtics in today's NBA). With a little digging you'll see he was a central piece in the trade that brought Maris to New York. All this from a coin.
The SC pins were so popular (after series upon series of movie starlets, flags and comic sayings) that American Tobacco produced them over three years (1910-12), with small and large letter variations for each pin (while I don't know for certain, I would guess that the Tris Speaker pin pictured here would be a 'small letter variation', while the Hal Chase would be a 'large letter variation').
The collector has to know a lot about baseball history to understand and enjoy baseball cards, but pins and coins make you work. Whereas a baseball card set generally gives you the whole story, neither of these sets--pins or coins--provide their subjects with any sort of context. It's the collector who has to fill in the blanks. And maybe that's why I count them among my favorite things: I'm willing to put in the work.