I don't think it'd be much of a problem.
If any guitar I was buying New had problems like that then I think you would find that most stores would throw in a setup or light work like this with the sale. Its the point of most stores havin a resident guitar tech. Sure he might self employed but theres always a "scratch my back, i'll scratch yours" policy going on with them.
It'd be easier than sending it back to distributor etc.
Sure it might be inconvenient for the store and they might get annoyed about it but the odd problem here and there is to be expected with wooden instruments.
Some shops here dont make a lot of money on F guitars for example so having to send a problem guitar back to distributor means that is their profit on that guitar gone. Cost of shipping could simply be the cost to repair. Its easier. Most resident guitar techs probably would fix a nut problem for the store for free anyway I expect.
This is just a broad overview of how I see it. Valid for problems with any guitar manafacturer I am pretty sure 99.9% of Sterlings are perfect.
