I don't think this is all that uncommon at his age - our kids' elementary school didn't allow the students to bring toys/etc to school because of issues with kids giving away things at recess that the parents didn't want given away
I'd also add - friendships among boys at that age are really pretty laid-back (at least among the boys I've known), and playdates usually happened more as a matter of either convenience among parents or happened because parents made sure they happened. Since it sounds like your ds has friends that he likes, I'd start asking a few of the boys over for playdates
Best wishes,
polarbear
