It'd probably matter if he wants to allow for the option of selling them if he ever needed to, or openning them one day. Not sure about how the batteries affect the plastic of the toy, but it'd most likely damage the electronic gimmick (as it did with my BotCon 2001 Arcee). But then again, if you have people buying the sealed toys in 10, 20+ years time, they can't complain about something that they should accept as being a standard issue with SEALED toys. If they want a guaranteed undamaged toy, they need to buy one that isn't sealed.