Hi E==
It appeared to me very hard to vote.
The answer varies widely depending on customer models of the SMEs, organizational sizes of the SMEs, trades of the SMEs and so forth.
If I dare to prepare an overall broad answer, I would say social media are less frequently utilized by SMEs than by large companies.
Social media are weak tools to force the customer to make the final decisions to purchase. Direct expressions and messages of classic type of ads are far much stronger to do so.
Large companies overall is well-known with the credit toward their brands. Customers of those companies need relatively weak push to purchase. On the other hand, SMEs and their products are not known well. So they have to convey more information than the large counterparts do and they have to have strong messages to make the customers buy.
Furthermore SMEs business resources are quite limited. In terms of marketing communication alternatives, SMEs often put more priority to ads than to social media.