Is there any শরعي (Shar'i) problem with receiving 'Umrah pilgrims with cars, children, and women, and with exchanging gifts with them, especially if a poor person burdens himself to buy them?

Receiving someone returning from Hajj or Umrah (definition) is a good and legitimate act. The Prophet, peace and blessings be upon him, was met by the children of the people of Madinah upon his return from a journey, and the boys of the Ansar met their families returning from Makkah. It is sunnah (definition) to greet the pilgrim, shake their hand, and ask them for prayers before they enter their home. Carrying gifts to those who come to meet them is also a good act that brings affection, as is giving gifts to them, provided that one does not burden themselves beyond their capacity.