i agree. in the infant sizes its a good idea to store extra, but you wont know till that special day what size you need. the hospital will send some home with you too. my first 2 were off the charts- 9.2 and 10.6. third was 8. never know lol.
same for new born clothes. get some basics, but remember they'll only be that size a matter of weeks. my first 2 started out at size 3mo lol. thats unusual, but you never know.