Birthday kid hurt my son's feelings

My son is in 6th grade and got invited to a birthday party from his soccer team. He was trying to find a gift and decided to buy the kid Pokemon cards. We went to the party. I got to talk to other adults. When they were opening gifts the kid got a lot of video games and an iPad. Etc. Etc. When my son gave him his gift not only did he hate it but made fun of it and said he's not 8. Why would he want Pokemon cards. I understand receiving something you don't want but I would never let my kids treat someone that way. The kid was super mean about it, causing other kids to be mean and the birthday boys mom did nothing about her son's because. After that they started excluding him and saying "This video game is for big kids. Go play with your Pokemon cards.": Even though they're the same age. So I took him home. He's really upset about everything. I know kids are into more technology now a days but again I would never allow my kids to treat someone who bought them something that way.