My mate picks up from his dealer 3-4-5 times a week, and so he likes him and gives him extra bud. So when i pick up with him we get loads more, last time i paid £20 for an 8th and ended up getting almost a 1/4 (6.2 grams he gave me)
He does this to keep us going back, which would make sense if he gave less each time.. but he doesn't, he keeps on giving Q's to people that buy regularly. My mate said he doesn't weigh out the bud, just gives you how much he thinks you deserve (say you paid £20 for an eighth, he would give you more, the better he knew you, he's never give anyone less than they pay for.)
Only thing that pisses me off about him is that he gets off work, for lunch at 1, and has to go back at about 1:30, so he deals to about 4/5 people in his lunch break, so you have to catch him as soon as he's off work, or he won't have time to get to you