Merchants don't adopt Bitcoin because their clients don't use it. Clients don't adopt it because merchants don't support it, and people want to have a payment method that can be used anywhere they go. How can this vicious circle be broken? Who will make the first move?
And by adopt I mean adopt for payments, not hodl it as an investment.
The vicious circle will be broken when the governments starts to re-define Bitcoin as a currency and not as a Commodity. Merchants cannot accept Bitcoin legally if their government does not accept it as legal tender. A lot of these merchants are doing this via Payment processors to bypass these restrictions.

Just have a look at what happened in El Salvador when their government accepted Bitcoin as legal tender.... the Merchants quickly started to accept Bitcoin as a payment option... even the large food chains like Mc Donald and Burger King.
