1. As long as the purchasing agent follows legal channels and does not purchase items that are prohibited from leaving the country, purchasing on behalf of others is not illegal. Purchasing on behalf of others does not constitute smuggling. Purchasing agents can also purchase in bulk.

2. Purchasing on behalf of others, in layman's terms, means finding someone to help you buy the goods you need. The reason may be that the goods are not available locally, the price of the goods in the local area is higher than that in other regions, or it can be to save personal time costs and ask someone to help buy and deliver to your door. Helping people buy goods from Hong Kong, Macau, Taiwan, and even the United States, Japan, France, and South Korea, and then shipping them by express delivery or bringing them back directly, or carrying goods from China to other countries is a common form of purchasing on behalf of others. There is also a kind of purchasing on behalf of others. Due to the lack of relevant information about the goods that consumers want to buy, they cannot determine their actual value and do not want to be slaughtered by merchants, so they have to entrust intermediaries to help them bargain for prices, or simply let intermediaries buy on their behalf.

3. The legal concept of smuggling refers to the violation of the Customs Law and other relevant laws and regulations of the country, evading customs supervision, illegally transporting, carrying, and mailing goods and articles prohibited from entering or leaving the country, restricted from entering or leaving the country, or subject to customs duties and other import tax collection in accordance with the law, with large amounts and serious circumstances.

4. In summary, the two are different, and legal purchasing is allowed.