Possible reasons:

• High costs of transactions — it's impractical especially in smaller, developing countries for costs of transaction for a single tx. Slower confirmation times too, is an inherent issue. There's almost no reason to transact in Bitcoin vs traditional payment methods
• Adoption rate still low despite decent growth — there is only a subtle increase in adoption of Bitcoin in developing countries.

Businesses survive if they make profit but they won't be able to price their goods at a favorable rate due to the additional costs bitcoin adds as transaction fees. Faster confirmation times and ultra low transactions fees will push bitcoin adoption by businesses.