Id say for discounts is the only reason why they would choose to do so.
Yes they will use for discounts and also because the transactions made with bitcoins are irreversible.
Discounts would be good for beginnings , but im not sure for this irreversoble part . Im not sure how you think that irreversible transactions is good for everyday for bitcoins ? What if you go to store and you acidently pay guy 0.01 insted of 0.001 ?
So I think that bitcoin can only work in the field of directed assembly. For daily use bitcoin is clearly still too early to say. As for the discount, the bitcoin and so provides many benefits.