I like Pokemon more than you! :p
I guess I'm the only one that has kept ever tin then haha I have like 30 I think1. You are forgetting one of the audiences for the tins: grandparents picking up a last minute gift that don't know any better. Hopefully they pick up a good one with ex/Vs.
2. As for keeping the tins my kids have kept 2 each. One for engery cards and one for the countless unused poison and burn counters.