When we speak of something being 'embedded' in social considerations, or even (a cumbersome and ugly phrase) 'embedded in the social', what we mean is that considerations of status and abstract relationships form part of the reasons for a particular action. 'The social', so-called (the influence of French academics should be obvious in the use of this hideous terminology), is often thought of as a disembodied milieu in which things happen; it is thought of as an over-arching whole encompassing human actions rather than just another set of reasons for action.
For instance: when a person gives a gift, very often the gift itself isn't important. What matters is that there is a relationship formed between the giver and the recipient such that they each feel more favourably to one another, or such that they will be more likely to help one another, or such that person A acquires prestige in the community relative to person B, or something similar. The gift itself is less important than the relationship, and so the act of gift-giving is often said to be 'embedded in the social'.
But in reality, the gift and the relationship are both important, but in differing degrees (imagine if you wanted to create a relationship with the Prime Minister by sending him a rotting rabbit carcass), and it is clear that social considerations are not separate from other reasons for action, nor are they different from them. The value of the gift, the status of the individual in the eyes of the community (status being generated by a recursive set of beliefs about beliefs), the value of forming a relationship with them in the first place, any number of other considerations - they all form reasons for action, and they all conflict with or support one another. It isn't that one set of reasons is 'embedded' in the others, as the popular terminology has it.
The notion of 'embeddedness' is common especially in economic anthropology, a sub-discipline that isn't really a sub-discipline at all. Karl Polanyi, and much more recently, David Graeber, have argued that economic transactions are 'embedded' in 'the social', and that this is part of the reason why markets are not a universal means for provisioning a society with goods and services; in many communities, economic transactions are also about kinship and status, and the abstract value of the goods concerned is unimportant relative to the relationship created by the transaction.
Polanyi made a prediction that markets were more likely to be found at the edges of communities, at the boundaries between groups - places where strangers are more likely to meet, and where exchange is more likely to take place between people who have relatively little interest in forming relationships with one another. In many cases, this prediction is true, as my tutor, R. H. Barnes, pointed out in a tutorial. Markets in the Solor archipelago are (or, until recently, were) almost universally found at the borders between communities. Only in these markets do the laws of supply and demand seem to function as supposed. Other economic transactions in the villages take place between people who have an interest in maintaining or creating a relationship and therefore do not involve exchange in the same sense - certainly the role of supply and demand is less important. From the perspective of strict economic rationalism, this method of provisioning society doesn't make a lot of sense, but that isn't the point. The transactions consist of rational acts and reasons for action nonetheless.
I don't believe we need the concept of 'embeddedness' to explain this. Nothing is 'embedded in the social'; ontologically speaking, this is absolutely unnecessary and ridiculous, and supposes that social events are somehow different from mental or physical events, somehow providing a milieu in which actions take place. Instead, I would explain the success of Polanyi's prediction, and of 'substantivist' economic anthropology, in terms of competing reasons for action, none of which provide a milieu for the others. When I exchange a product with someone I don't know and have no reason to care much for, then the abstract value of the transaction is, of course, the most important variable. If I exchange something with my parents or partner or a friend, I have to care about other things, but that doesn't mean that any of these things is 'embedded' in any of the others. They're all competing reasons for action. They supplement or conflict with one another. It so happens that so-called 'social' considerations are important in causing human actions, but they aren't all-important.