Part of the problem is no one is selling more then 4oz bottles of the stuff other then Capella itself. And even the number of sites that sell the 4oz are very limited. So if anyone makes a ton of VC juice they might grab 2 or more 4oz bottles at a time. The vendors probably only get around 50 or less which means potentially only 30 people might actually be able to get some each week. Plus there are a ton of hole in the wall smoke/vape shops buying from DIY suppliers too.
Right now people are also stocking up just in case something changes and the v1 disappears. So the odds of getting your hands on a bottle of Cap VC or even some of the Harvest Berry are pretty bad. If vendors would just buy more and flood the market they would make more profit and there would be no more shortages. But I believe vendors want it to seem scarce so people will buy more and stock up simply to net them quicker short term profit.