Title is the question, question is close this one, however there might be more information available specifically for planting.
The price and quantity of sprouting seeds seem to, by and large, have significant differences, spouting seeds usually are packaged in large orders on a much more reasonable per unit price, compared to one seeds offered at large home improvement stores. The difference seems to be, at least for this retailer, in the farmer/suppliers process deemed to specifically distinguish sprouting from for-planting seeds.
If there is a fundamental difference are there wholesalers for plant seeds?