Small shoes mean small feet.
During ancient times, Chinese men found women with small feet to be particularly attractive. Since women with small feet were considered more attractive, their chances of finding a husband were enhanced.
Therefore, a “small shoe” charm should bring good luck in finding a husband.
You must understand that by “small” feet we mean really small. In this case, we are talking about a total foot length of about 3 inches from toes to heel. This did not occur naturally but was accomplished through the barbaric practice of foot-binding.
For a girl, foot-binding started at a very young age, usually at 3-5 years of age, and continued for the rest of her life. It was an extremely painful process where the foot was bound in such a way that the toes were forced down and back towards the heel.
Such small feet were referred to as “lotus feet” and the small shoes that were worn were called “lotus shoes”.
Girls with bound-feet were considered more desirable for a number of reasons. Because they could not walk normally, they were perceived to be of a “higher status” since they did not have to work in the fields like the vast majority of girls.
Men also found women with bound feet to have more sex appeal for several reasons.
One reason was that women with bound-feet walked in a swaying and seductive manner similar to women who wear high heels.
Also, men believed a woman’s foot was, in a sense, the center of sexuality which should be covered from public view. Even more importantly, it was believed that foot-binding made a women’s vagina narrower and thus provide more pleasure to the man during sexual intercourse.
As a consequence, a woman with bound feet would have more chances to become pregnant and give birth to more male babies which, in a traditional Confucian culture, would bring her more prestige.
Families realized that they would have a better opportunity to improve their own status if their daughters married well and produced male offspring so even poor families wanted for their daughters to be foot-bound if possible.
As I mentioned earlier, I am not familiar with the small shoe charm you purchased so the above discussion is just speculation on my part concerning the possible origin of such a custom.
In conclusion, I would like to mention that shoes were an important symbol in other areas of ancient Chinese culture as well. Shoes were a symbol of wealth (resemble silver ingots) and fertility as I explain at “Hidden Meaning of Chinese Charm Symbols” and shoes also played an important role in the traditional marriage ceremony as discussed at Ancient Chinese Marriage Charms.