LOL, yeah I have a tiny bit of a problem with impulse control. Also, it's because I am a newbie (just started in April) and everything is so pretty and sooo hard to resist!
I paper scrapbook and do project life too. Price wise, this ends up being such a small amount of money compared to purchasing physical supplies. I do try to keep all of my orders well under $20 when I shop (unless it's on release day, the week that we get the big coupon or when there is a really good sale). In my mind... if an order is under $20 it's like, well it's only 11.50 it's nothing... and I will do that all week. Then at the end of the month I'm like, wow those under $20 sales add up!